UNIVERSITY  OF  CALIFORNIA 

DEPARTMENT  OF  CIVIL  ENGINEERING 

BERKELEY.  CALIFORNIA 


UNIVERSITY  OF  CALIFORNIA 

DEPARTMENT  OF  CIVIL  ENGINEERING 

BERKELEY.  CALIFORNIA 


OPERATION  AND  MAINTENANCE 

OF 

IRRIGATION  SYSTEMS 


STANDARD   IRRIGATION  BOOKS 

PUBLISHED  BY 

McGRAW-HILL    BOOK   COMPANY,    INC. 

239  WEST  39TH  ST.,  NEW  YORK  CITY 

IRRIGATION  PRACTICE  AND 
ENGINEERING 

BY  B.  A.  ETCHEVERRY 

VOL.      I. — USE   OP  IRRIGATION  WATER 
AND  IRRIGATION  PRACTICE. 
213  pages,  6x9,  over  100  Illustrations.  .  $2.00 

VOL.    II. — CONVEYANCE  OP  WATER. 
364  pages,  6x9,  over  100  Illustrations.  .  $3.50 

VOL.  III. — IRRIGATION  STRUCTURES  AND 

DISTRIBUTION  SYSTEMS. 
438  pages,  6x9,  over  200  Illustrations.  .  $4.00 
A  COMPANION  VOLUME 

HARDING:  OPERATION  AND  MAINTENANCE 

OP  IRRIGATION  SYSTEMS. 
271  pages,  6x9,  25  Illustrations $2.50 


OPERATION  AND  MAINTENANCE 


OF 


IRRIGATION  SYSTEMS 


BY 
S.  T.  HARDING 

OF 


ASSISTANT  PROFESSOR   OF   IRRIGATION,   UNIVERSITY   OF 

CALIFORNIA,  FORMERLY   IRRIGATION   ENGINEER 

U.  S.   DEPARTMENT  OF  AGRICULTURE. 


FIRST  EDITION 
SECOND  IMPRESSION 


McGRAW-HILL  BOOK  COMPANY,  INC, 

239  WEST  39TH  STREET.    NEW  YORK 


LONDON:  HILL  PUBLISHING  CO.,  LTD. 
6  &  8  BOUVERIE  ST.,  E.  C. 

1917 


h)3 


Engineering 
Library 


COPYRIGHT,  1917,  BY  THE 
McGRAW-HiLL  BOOK  COMPANY,  INC. 


THE  MAPLE  PRESS  YORK  PA 


PREFACE 

The  operation  and  maintenance  of  irrigation  systems  is  a 
subject  of  very  active  interest  in  the  western  states.  The  large 
number  of  irrigation  systems  constructed  during  the  past  15  years 
have  served  to  call  attention  to  the  importance  of  questions  of 
operation  policies  and  methods.  Relatively  such  questions  are 
at  present  much  less  thoroughly  worked  out  than  the  strictly 
engineering  questions  of  design  and  construction. 

This  volume  is  the  outgrowth  of  notes  prepared  for  class  use  in  a 
course  in  this  subject  given  by  the  author  at  the  University  of 
California.  It  is  based  on  several  years  personal  experience  and 
observation  in  irrigation  work  in  many  of  the  western  states,  and 
on  a  careful  examination  of  available  published  material  supple- 
mented by  correspondence  and  discussions  with  many  of  those 
connected  with  the  operation  and  maintenance  of  irrigation 
systems. 

The  subject  of  this  volume  is  necessarily  one  of  practice  rather 
than  of  theory.  As  in  other  similar  subjects,  practice  is  mate- 
rially affected  by  local  conditions,  which  in  irrigation  may  vary 
widely  in  the  different  irrigated  sections.  Such  variations  make 
it  difficult  to  distinguish  the  principles  of  the  practice  from  the 
local  application  of  such  principles.  An  attempt  has  been  made 
to  give  the  general  principles  that  may  be  recognized,  illustrated 
by  typical  examples  of  their  local  application,  rather  than  to 
fully  cover  all  local  variations  in  practice.  No  attempt  has  been 
made  to  cover  practice  outside  of  the  United  States. 

There  is  very  little  published  material  relating  to  this  subject 
which  is  generally  available.  References  to  the  more  important 
articles  are  given  at  the  end  of  each  chapter;  many  of  these,  how- 
ever, have  had  only  a  limited  distribution  and  will  be  available 
to  only  a  few  readers.  Formal  references  to  much  other  material 
found  to  be  valuable  in  the  preparation  of  this  volume  are  not 
given  as  these  consist  of  unpublished  reports  or  other  material 
of  similar  nature.  The  author  also  desires  to  express  his  obliga- 
tion to  those  who,  both  by  correspondence  and  by  facilities  for 
examination  during  visits  to  their  systems,  have  been  of  assistance 
in  the  collection  of  the  data  on  which  many  of  the  discussions  in 


vi  PREFACE 

this  work  are  based.  A  greater  amount  of  data  regarding  the 
systems  of  the  U.  S.  Reclamation  Service  has  been  published  than 
for  other  forms  of  organizations,  and  to  many  members  of  this 
organization  particular  thanks  are  due.  Material  has  also  been 
secured  from  systems  operating  under  all  forms  of  organization  in 
order  that  the  treatment  might  be  generally  representative.  His 
indebtedness  to  all  such  sources  is  gratefully  acknowledged. 

SIDNEY  T.  HARDING. 
BERKELEY,  CAL., 
July,  1917 


CONTENTS 

PAGE 
PREFACE    v 

LIST  OF  PLATES    . xi 

CHAPTER  I 

GENERAL  MAINTENANCE    . 1 

DAMAGES  FOR  FAILURE  TO  MAINTAIN — MAINTENANCE  OF  CANALS 
—Priming  Canals — Canals  in  Unstable  Formations — OVERTOP- 
PING CANAL  BANKS — Protection  Against  Canal  Erosion — SILT 
OR  SEDIMENT  IN  CANALS — Artificial  Silting — Removal  of  Excess 
Silt — AQUATIC  GROWTHS — Kinds  of  Aquatic  Growths — METHODS 
OF  HANDLING  AQUATIC  GROWTHS — Cutting — Dragging — Harrow- 
ing— Miscellaneous  Methods — SEMI-AQUATIC  PLANTS — VEGETA- 
TION ON  CANAL  BANKS — Native  Plants — GENERAL  METHODS  OF 
CONTROL  OF  VEGETATION  ON  CANAL  BANKS — Grazing — Mowing — 
Chemical  Control — Seeded  Grasses — Miscellaneous  Methods — 
PROTECTION  OF  CANALS  IN  BLOWING  SOILS — CANAL  SCREENS — 
BURROWING  ANIMALS — Pocket  Gophers — Ground  Squirrels — 
Muskrats — Other  Animals — METHODS  OF  CONTROL  OF  BURROW- 
ING ANIMALS — Poisoning — Trapping — Suffocation — Natural  Con- 
trol— Special  Methods — FENCING  CANAL  RIGHTS  OF  WAY — Legal 
Fences — Cost  of  Fences — REFERENCES  FOR  CHAPTER  I. 

CHAPTER  II 

MAINTENANCE  OF  IRRIGATION  SYSTEMS 50 

MAINTENANCE  OF  STRUCTURES — SERVICEABLE  LIFE  OF  IRRIGATION 
STRUCTURES — Wood  Structures — Life  of  Wood  Flumes — Life  of 
Woodstave  Pipe — Life  of  Wood  Structures — Life  of  Concrete  Struc- 
tures— Life  of  Steel — SELECTION  OF  TYPE  OF  STRUCTURES — MAINTE- 
NANCE OF  RESERVOIRS — MAINTENANCE  OF  DIVERSION  DAMS  AND 
HEADWORKS — MAINTENANCE  OF  GENERAL  STRUCTURES — Erosion 
of  Canals  Adjacent  to  Structures — Cutting  Around  Structures 
— MAINTENANCE  OF  FLUMES — MAINTENANCE  OF  CONCRETE-LINED 
CANALS — BRIDGES — TELEPHONES — REFERENCES  FOR  CHAPTER  II. 

CHAPTER  III 

ORGANIZATION  FOR  OPERATION  AND  MAINTENANCE 79 

Organization  Divisions — General  Supervision — Direct  Supervision 
OPERATION  DIVISION — DITCH  RIDERS — Area  Handled  per  Ditch 
Rider — Delivery  to  Individuals — Delivery  to  Laterals  Only — Sum- 

vii 


viii  CONTENTS 

PAGB 

mary    of   Area   Handled   per   Ditch   Rider — Length   of   Beats — 
Compensation  of  Ditch  Riders — Patrolmen — ENGINEERING  DIVI- 
SION— CLERICAL  DIVISION — SIZE  OF  ORGANIZATION — REFERENCES  ' 
FOR  CHAPTER   III. 

CHAPTER  IV 

METHODS  OF  DELIVERING  IRRIGATION  WATER 99 

Legal  Definitions — CONTINUOUS  DELIVERY — ROTATION  DELIVERY 
— Rotation  Schedules — Rotation  between  Laterals — Delivery  Up  or 
Down  Laterals — Fixed  and  Flexible  Rotation  Schedules — Delivery 
during  Shortage — DELIVERY  ON  DEMAND — SPECIAL  METHODS — 
MEASUREMENT  OF  DELIVERY — FORMS  USED  FOR  THE  DELIVERY 
OF  WATER — Forms  of  Application  for  Water  Delivery — Forms  for 
Notices  to  Consumers  Regarding  Delivery — SUMMARY  OF  DELIVERY 
METHODS — CONTROL  OF  LATERALS — Examples  of  Practice — REFER- 
ENCES FOR  CHAPTER  IV. 

CHAPTER  V 

MEASUREMENT  OF  IRRIGATION  WATER 125 

CANAL  HYDROGRAPHY — Requirements  of  Canal  Rating  Stations — 
Equipment  of  Gaging  Stations — Rating  Stations  not  Subject  to 
Control — METHODS  OF  CANAL  MEASUREMENT — Current-meter 
Practice — Use  of  Surface  Floats — Number  of  Points  of  Observa- 
tion—Cages— Notes  and  Records — MEASUREMENT  OF  INDIVIDUAL 
DELIVERIES — Conditions  Affecting  Accuracy — Cost  of  Operation  of 
Measuring  Devices — Other  Requirements  of  Measuring  Devices 
— WEIRS — SUBMERGED  ORIFICES — SPECIAL  MEASURING  DEVICES 
— RECORDS  OF  INDIVIDUAL  DELIVERIES — Computations — Forms 
— Ditch  Riders'  Records — Water  Ledger  Cards — REFERENCES 
ON  MEASUREMENT  OF  WATER. 

CHAPTER  VI 

RULES  AND  REGULATIONS 173 

Control  of  Canal  System — Access  to  Land — Location  of  Gates — 
Rights  of  Way — Maintenance  of  Laterals — Delivery  of  Water — 
Application  for  Water — Minimum  Period  of  Delivery — Measure- 
ment of  Water — Apportionment  in  Time  of  Shortage — Interrup- 
tions in  Service — Stock  Water — Waste — Terms  of  Payment — Com- 
plaints— Liability  of  Company — Liability  of  Irrigator — Penalty 
for  Breaking  Rules — Miscellaneous  Rules. 

CHAPTER  VII 

PAYMENT  FOR  CONSTRUCTION  AND  OPERATION  CHARGES 187 

CONSTRUCTION  CHARGES — Apportionment  of  Construction  Costs — 
Effect  of  Form  of  Organization — Comparison  of  Flat  Rate  and 


CONTENTS  ix 

PAGE 

Benefit  Charges — Classification  of  Irrigable  Area — Terms  of  Pay- 
ment— OPERATION  AND  MAINTENANCE  CHARGES — Limits  of 
Beneficial  Use — Factors  Affecting  Use  of  Water — Effect  of  Rates  on 
Measurement  of  Water — FLAT  RATES — QUANTITY  RATES — Clas- 
sification of  Operation  and  Maintenance  Costs — Ratio  of  Demand 
and  Service  Costs — Variations  in  Rates  from  Cost  of  Service — Varia- 
tions in  Rates  due  to  Soil  Conditions — TERMS  OF  PAYMENT — SUM- 
MARY— REFERENCES  FOR  CHAPTER  VII. 

CHAPTER  VIII 

GENERAL  OPERATION 209 

USE  OF  CHECKS  IN  CANALS — WASTE  WATER  FROM  FARMS — WASTE- 
WAYS — STOCK  WATER — NUMBERING  CANALS  AND  TURNOUTS — 
LOCKING  TURNOUTS — WINTER  OPERATION — COMPLAINTS — CROP 
STATISTICS — DRAINAGE — DELIVERY  OF  STORAGE  THROUGH  STREAMS 
— OPERATION  OF  LARGE  PUMPING  PLANTS — Canal  Operation 
Under  Pumping  Plants — Equipment  of  Pumping  Plants — Opera- 
tion of  Pumping  Plants — Source  of  Power — Cost  of  Pumping — RE- 
LATIONS OF  OPERATION  ORGANIZATION  AND  LAND  OWNERS — Colo- 
nization— Methods  of  Land  Colonization  are  Improving — Average 
Size  of  Farm — Agricultural  Aid  to  Irrigators — Ownership  of  Land 
by  Operation  Force — Restricting  Use  of  Water — Determination  of 
Operation  Policy — REFERENCES  FOR  CHAPTER  VIII. 

CHAPTER  IX 

OPERATION  AND  MAINTENANCE  ACCOUNTS 243 

GENERAL  CLASSES  OF  ACCOUNTS — ACTUAL  ACCOUNTS — REPORTS 
— Annual  Reports — Circulars — Records — REFERENCES  FOR  CHAP- 
TER IX. 

APPENDIX 

RULES  AND  REGULATIONS 257 

IDAHO  IRRIGATION  DISTRICT — TURLOCK  IRRIGATION  DISTRICT — SAN 
Luis  POWER  &  WATER  COMPANY — FRESNO  CANAL  AND  IRRIGATION 
COMPANY. 

INDEX . 267 


LIST  OF  PLATES 

Facing  page 

PLATE  I 12 

FIG.  A. — Eroded  bank  in  sandy  soil,  before  lining,  Main  canal, 

Minidoka  project. 
FIG.  B. — Main   canal,    Minidoka  project,  lined  with   sage  brush 

preparatory  to  silting. 

FIG.  C. — Brush  riprap  used  in  the  Imperial  Valley. 
FIG.  D. — Willows  used  to  reduce  erosion,  Snow  Lateral,  Billings, 

Mont. 

PLATE  II 16 

FIG.  A. — Silting  above  checks,  Imperial  Valley. 

FIG.  B.— Canal  "V"  used  to  remove  silt,  Imperial  Valley. 

FIG.  C. — Canal  in  Imperial  Valley  shortly  after  cleaning  value  of 

n  =  0.022. 
FIG.  D. — Similar  canal  to  that  shown  in  Fig.  C.  with  excessive 

growth  of  vegetation,  value  of  n  =  0.029  (Figs.  C  and  D 

from  Bull.  194,  U.  S.  Dept.  of  Agric.). 

PLATE  III 26 

FIG.  A. — Aquatic  vegetation  in  a  canal  in  San  Joaquin  Valley, 

California. 

FIG.  B. — Vegetation  at  sides  of  canal,  causing  silt  berms. 
FIG.  C. — Removing  moss  from  a  lined  canal  in  Southern  California. 
FIG.  D. — Sweet  clover  on  canal  banks,  Big  Ditch,  Montana. 

PLATE  IV 62 

FIG.  A. — Side  hill  canal  with  retaining  wall  used  to  replace 
wood  bench  flume,  Hedge  Canal,  Montana. 

FIG.  B. — Lined  canal  on  hydraulic  fill  used  to  replace  wood  flume, 
Turlock  Irrigation  District. 

FIG.  C. — Concrete  flume  in  light  fill  in  sandy  soil,  Crocker- 
Huffman  Land  and  Water  Co.,  California. 

FIG.  D. — Concrete  arch  flume  used  to  replace  wood  flume,  Modesto 
Irrigation  District. 

PLATE  V ,    .   .   .    .     68 

FIG.  A. — Light  wood  check  weighted  to  prevent  floating. 

FIG.  B. — Erosion  below  structure. 

FIG.  C. — Erosion  below  drop,  Lateral  on  Worth  Platte  project, 

Nebraska. 

FIG.  D. — Erosion  below  drop,  Modesto  irrigation  district. 

xi 


xii  LIST  OF  PLATES 

Facing  Page 

PLATE  VI 148 

FIG.  A. — Eighteen-inch  Cippoletti  Weir. 

FIG.  B. — Weir  with  gage  graduated  to  read  discharge  directly, 

Twin  Falls  Salmon  River  System. 
FIG.  C. — Headgate  with  sharp  edged  orifice  set  in  front  wall,  Mini- 

doka  project. 
FIG.  D. — Dethridge  Meter  installed  in  laboratory  of  California 

Experimental  Station  at  Davis. 
FIG.  E. — Double  orifice  headgate  graduated  to  show  discharge  in 

miners'  inches,  used  in  Idaho. 


OPERATION  AND  MAINTENANCE 

OF 

IRRIGATION  SYSTEMS 

CHAPTER  I 
GENERAL  MAINTENANCE 

The  term  maintenance,  as  generally  used,  includes  repairs, 
replacements  and  betterments.  Repairs  are  the  routine  and 
generally  minor  work  done  on  canals  and  structures  in  order  to 
maintain  their  usefulness.  Even  with  proper  care  in  repairs, 
renewals  of  structures  will  eventually  be  required.  Where  a  new 
structure  has  the  same  capacity  and  is  of  the  same  type,  it  is 
classed  as  a  replacement ;  where  a  more  permanent  type  of  con- 
struction is  used  or  where  a  large  capacity  is  secured,  it  is  classed 
as  a  betterment.  The  definition  of  these  terms  and  the  methods 
of  handling  maintenance  accounts  are  discussed  in  more  detail 
in  Chapter  IX.  Routine  maintenance  such  as  repairs  and 
smaller  replacements  is  handled  by  the  regular  operation  organi- 
zation. Extensive  replacements  or  betterments  are  more  largely 
questions  of  engineering  design  and  construction  which  are 
similar  to  those  involved  in  the  original  development  of  the 
system.  Such  work  is  usually  handled  by  an  engineering  or- 
ganization similar  to  that  used  during  the  original  construction 
period. 

There  is  little  definite  data  available  regarding  the  cost  of 
maintenance.  On  any  system  such  costs  will  vary  quite  widely  in 
different  years.  On  some  canals  the  separation  of  the  costs  of 
operation  and  maintenance  expenditures  may  not  be  attempted. 
Where  such  segregations  are  made,  the  method  of  classification 
varies.  Costs  for  maintenance  are  usually  expressed  in  terms  of 
the  cost  per  mile  of  canal  operated  or  per  acre  served.  For  com- 
parisons of  the  economy  of  structures  of  different  types  annual 
maintenance  costs  expressed  as  a  percentage  of  the  first  cost  of 
the  structure  are  most  convenient.  For  canal  cleaning  the  cost 
per  mile  of  canal  forms  the  more  logical  basis  for  comparison. 

1 


2  IRRIGATION  SYSTEMS 

Maintenance  costs  per  acre  served  may  not  furnish  a  satisfactory 
basis  of  comparison  for  different  canal  systems  due  to  differences 
in  conditions  which  are  not  proportional  to  the  acreage.  Acre- 
age costs,  however,  are  useful  in  determining  charges  as  the  area  is 
more  usually  the  unit  to  which  the  costs  or  payments  to  be  made 
are  distributed. 

The  13th  U.  S.  Census  in  1910  secured  data  on  the  cost  of  opera- 
tion and  maintenance  from  systems  serving  about  one-half  of  the 
irrigated  area.  The  companies  from  which  data  were  obtained 
were  mainly  the  larger  systems.  For  all  the  States  the  average 
annual  cost  of  operation  and  maintenance  was  $1.07  per  acre,  the 
minimum  average  for  a  State  being  63  cents  for  Idaho  and  the 
maximum  $3.25  for  Texas.  For  many  systems,  it  is  probable 
that  the  costs  given  did  not  include  all  expenses  for  operation 
and  maintenance. 

In  connection  with  its  supervision  of  public  utility  irrigation 
companies,  the  California  Railroad  Commission  has  secured  rec- 
ords of  the  costs  of  operation  and  maintenance  of  a  number  of 
such  companies.  For  16  companies  which  have  come  before  the 
Commission  for  rate-fixing  purposes  the  average  cost  per  acre  for 
general  salaries  was  63  cents,  other  general  expenses  21  cents, 
taxes  16  cents,  operation  97  cents,  maintenance  59  cents,  a  total 
of  $2.56  per  acre.  The  variations  in  these  figures  for  particular 
systems  were  naturally  quite  large.  The  average  cost  per  mile 
of  canal  for  operation  was  $64  and  for  maintenance  $52,  the 
total  including  general  expenses  being  $174.  These  systems  had 
a  total  irrigated  area  of  118,000  acres  and  a  length  of  canal  of 
1300  miles.  The  reports  for  1914  of  24  companies  gave  an  aver- 
age of  $1.78  per  acre  irrigated  and  $267  per  mile  of  canal  oper- 
ated for  the  total  cost  of  operation  and  maintenance  including 
general  expenses.  The  average  cost  per  acre  for  operation  was 
50  cents  and  for  maintenance  61  cents.  The  average  cost  per 
mile  of  canal  was  $91  for  operation  and  $75  for  maintenance. 
These  reports  covered  an  irrigated  area  of  over  500,000  acres 
and  a  length  of  canal  of  over  1,000  miles.  The  figures  for  indi- 
vidual companies  also  varied  widely. 

The  accounts  of  the  U.  S.  Reclamation  Service  distinguish 
operation  and  maintenance  costs.  Their  fiscal  year  ends  June  30, 
so  that  the  figures  given  in  their  present  annual  reports  do  not 
give  costs  for  the  actual  operation  year.  The  total  costs  for 
operation  and  maintenance  to  June  30, 1916,  are  given  in  the  15th 


GENERAL  MAINTENANCE 


Annual  Report.     These  have  been  used  to  compute  the  percent 
age  given  in  Table  I. 

TABLE   I. — DISTRIBUTION   OF   OPERATION   AND    MAINTENANCE   COSTS   TO 

DATE  ON  ALL  PROJECTS  OF  THE  U.  S.  RECLAMATION  SERVICE  TO 

JUNE  30,  1916 


Per  cent,  of 
total  operation 

Per  cent,  of 
total    main- 
tenance 

Per  cent,  of 
total  operation 
and  mainte- 
nance 

Ratio  of  opera- 
tion to  main- 
tenance 

Storage  works  

11 

7 

8 

0  75 

Canal  system..  
Lateral  system. 

26 

52 

27 
53 

27 
52 

0.51 
0  50 

Drainage  system  
Flood      protection 
system. 

2 

o 

3 

o 

3 

o 

0.25 
0  10 

Undistributed  expenses 

9  . 

10 

10 

0.46 

Total  

100 

100 

100 

0.62 

The  operation  and  maintenance  results  for  1912  have  been  sepa- 
rately published  in  more  detail  than  those  for  later  years.  The 
average  cost  for  acre  irrigable  for  all  projects  was  36  cents  for  opera- 
tion, 56  cents  for  upkeep  and  35  cents  for  betterments.  An  aver- 
age of  only  54  per  cent,  of  the  irrigable  area  was  actually  irrigated 
in  this  year  so  that  the  cost  per  acre  actually  irrigated  would  be 
nearly  double  the  figures  given.  The  figures  cover  a  wide  range  of 
conditions  but  generally  represent  systems  in  the  earlier  periods  of 
development.  There  were  5,744  miles  of  canal  operated  at  an 
average  cost  per  mile  of  $74  for  operation,  $117  for  upkeep  and 
$73  for  betterments,  a  total  cost  of  $263  per  mile.  On  the  differ- 
ent systems  the  costs  of  these  items  varied  by  several  hundred  per 
cent,  in  some  cases.  Such  variations  are  due  to  such  local  con- 
ditions as  length  of  operation  season,  character  of  service  given, 
topography,  character  of  the  soil,  canal  vegetation  and  the  extent 
of  silting. 

These  general  figures  are  illustrative  of  the  average  costs  on 
typical  systems.  On  small  or  loosely  handled  canals  the  costs  of 
operation  and  maintenance  may  be  as  low  as  50  cents  per  acre  per 
year.  Under  favorable  conditions  on  large  well-developed  and 
maintained  systems  the  direct  annual  cost  of  operation  and 
maintenance  exclusive  of  interest  and  depreciation  may  be  less 
than  $1  per  acre.  In  many  pases  such  costs  will  be  from  $1  to  $2 


4  IRRIGATION  SYSTEMS 

per  acre.  Where  long  diversion  canals  or  other  difficult  con- 
struction are  needed,  where  storage  or  pumping  are  required, 
where  the  operation  season  is  long,  or  where  silt  or  vegetation  are 
unusually  expensive  to  handle,  the  costs  of  operation  and  main- 
tenance may  exceed  $2  per  acre. 

The  costs  of  maintenance  per  mile  of  canal  for  usual  conditions  is 
generally  from  $50  to  $100  per  mile.  Where  excessive  silting  or 
vegetation  or  other  unfavorable  conditions  are  encountered  the 
cost  may  exceed  $200  per  mile.  In  1915,  cleaning,  clearing 
and  repairs  cost  an  average  of  $375  per  mile  on  the  335  miles  of 
the  Imperial  Water  Co.  No.  1.  The  natural  conditions  of  this 
system  are  extremely  unfavorable  in  regard  to  silt  and  vegetation. 
For  canals  having  short  operation  seasons  with  little  silting  or 
vegetation  the  annual  cost  of  maintenance  may  be  less  than  $50 
per  mile. 

DAMAGES  FOR  FAILURE  TO   MAINTAIN 

The  extent  of  the  responsibility  of  the  canal  owner  for  damages 
which  may  result  from  canal  breaks  or  seepage  differs  somewhat 
in  different  States  and  involves  a  number  of  legal  points.  Any 
actual  cause  for  complaint  should  be  handled  by  the  cooperation 
of  the  operation  and  legal  organization.  In  addition  to  legal 
points  as  to  responsibility,  a  jury  trial  in  any  particular  case 
introduces  an  element  of  uncertainty  as  to  the  value  which  may 
be  assigned  to  the  injury. 

Irrigation  companies  are  not  insurers  and  are  liable  only  for 
such  injuries  to  others  as  result  from  their  own  negligence  and  the 
failure  to  use  reasonable  care  and  skill  in  construction  and  opera- 
tion. The  care  required  to  be  used  is  that  which  ordinarily 
prudent  men  exercise  under  like  circumstances  when  the  risk  is 
their  own.  This  applies  both  to  canal  breaks  and  to  general 
canal  seepage.  A  canal  company  is  not  required  to  entirely  pre- 
vent seepage  from  a  canal;  the  skill  in  construction  and  operation 
must  be  such  that  the  amount  of  the  seepage  does  not  exceed  that 
found  on  well-maintained  canals  in  similar  material.  The  dili- 
gence and  care  used  in  preventing  damage  should  be  proportional 
to  the  risk  to  others.  Canal  owners  are  not  responsible  for  dam- 
ages due  to  acts  of  God  which  are  of  such  unusual  nature  that  one 
cannot  be  expected  to  foresee  their  occurrence  or  be  able  to  pre- 
vent the  injury  caused.  Breaks  caused  by  cloudbursts  on  lands 
above  the  canals  or  floods  of  rare  occurrence  may  be  classed  as 


GENERAL  MAINTENANCE  5 

such  acts  of  God.  The  canal  owner  may  be  held  responsible  for 
damages  caused  by  floods  of  such  frequency  that  their  occurrence 
should  have  been  foreseen.  There  is  much  difference,  in  the  re- 
covery of  damages  against  systems  in  private  ownership  as  com- 
pared with  recovery  against  systems  owned  by  the  government. 
The  government  can  be  sued  only  with  its  consent  and  has  con- 
sented to  be  sued  only  through  the  Court  of  Claims  in  suits  arising 
in  contract  and  not  in  suits  arising  in  tort,  such  as  those  for 
damages.  Individual  officers  of  the  government  are  liable  only 
for  their  own  wrongful  act  and  not  for  the  defective- condition  of 
government  property. 

Damages  are  limited  to  the  value  of  the  actual  injury  and  the 
extent  of  damage  must  be  proven  by  the  one  injured.  The  one 
injured  must  use  reasonable  diligence  to  minimize  the  resulting 
injury  and  cannot  recover  for  damages  which  he  could  have  pre- 
vented. If  land  is  destroyed,  such  as  by  erosion  from  a  canal 
break,  so  as  to  have  no  remaining  value,  the  cash  value  at  the 
time  of  destruction  measures  the  amount  of  the  damage.  If 
permanently  injured  but  not  wholly  destroyed,  the  damages  are 
measured  by  the  loss  in  cash  value  or  the  difference  in  value  before 
and  after  injury.  If  only  temporarily  injured,  the  cost  of  restor- 
ing the  land  to  its  previous  condition  may  be  a  measure  of  the 
difference  in  value  or  the  damage  to  the  land.  For  the  destruc- 
tion of  crops  the  damage  is  measured  by  the  value  of  the  crop  at 
the  time  of  its  destruction. 

The  above  discussion  covers  damages  due  to  an  actual  injury 
to  the  land.  The  damage  to  relatively  large  areas  from  the  in- 
ability to  deliver  water  due  to  a  canal  break  may  be  much  greater 
than  the  direct  injury  to  lands  adjacent  to  the  break.  Where 
such  failure  to  deliver  prevents  planting  a  crop,  the  damages  are 
measured  by  the  difference  in  the  rental  value  of  the  land  with 
and  without  water.  Evidence  in  regard  to  crops  that  might  have 
been  grown  is  too  uncertain  and  speculative.  Damages  due  to 
failure  to  deliver  water  are  usually  covered  by  the  terms  of  the 
water-right  contract  in  the  case  of  systems  owned  by  others  than 
the  land  owners,  the  contracts  containing  clauses  specifying  the 
penalty  or  exempting  the  canal  company.  Where  the  canal  system 
is  owned  by  the  land  owners,  damages  for  general  failure  to 
deliver  water  are  not  usual  as  those  injured  and  those  responsible 
have  the  same  general  identity. 

Several  of  the  States  have  statutes  requiring  canal  owners   to 


6  IRRIGATION  SYSTEMS 

maintain  the  embankments  of  the  ditches  so  that  no  injury  will 
be  caused  to  others.  Such  statutes  serve  to  emphasize  the  need 
of  diligence  and  skill  rather  than  to  change  the  extent  of  the 
liability  previously  mentioned.  Some  States  also  specify  that  a 
tail  ditch  shall  be  provided,  the  purpose  being  to  prevent  injury 
from  overflow  at  the  lower  ends  of  canals.  The  canal  owner  is 
responsible  for  injury  that  may  be  caused  by  waste  water  from  the 
canal ;  the  land  owner  for  damages  caused  by  waste  water  escap- 
ing from  farms  after  it  has  been  delivered  by  the  canal  company. 
In  some  cases  the  liability  for  damages  is  considered  to  be  differ- 
ent when  caused  by  water  flowing  in  canals  than  when  caused  by 
water  retained  in  reservoirs,  in  that  negligence  does  not  need  to  be 
proven  to  the  same  extent  in  the  cases  of  breaks  in  reservoirs. 

MAINTENANCE  OF  CANALS 

Priming  Canals. — Much  care  is  needed  in  running  water  for  the 
first  time  in  new  canals  as  the  banks  of  the  canal  and  backfill 
around  the  structures  will  not  be  packed  and  settled.  No  amount 
of  care  in  construction  will  make  it  safe  to  bring  canals  too  quickly 
under  the  strain  of  full  depth  of  flow.  If  a  small  depth  can  be 
carried  for  a  relatively  long  time,  the  banks  will  absorb  moisture 
and  become  settled ;  weaknesses  can  be  detected  and  repaired  with 
less  damage;  holes  of  burrowing  animals  can  be  found  and  closed; 
and  cutting  around  structures  may  be  repaired  before  the  struc- 
ture itself  is  injured.  It  may  require  several  weeks  use  before  new 
canal  banks  will  become  sufficiently  saturated  to  develop  weak- 
ness. If  conditions  will  permit  the  priming  of  a  new  canal  during 
the  season  before  its  use  for  actual  delivery  of  water,  much 
better  results  can  usually  be  obtained.  The  settlement  during 
the  following  winter  is  also  a  material  advantage.  Where  check- 
ing the  flow  in  the  canal  is  not  necessary,  a  new'  canal  may  not 
be  required  to  carry  the  full  depth  of  flow  for  1  or  more  years 
depending  on  the  rate  of  development.  If  checking  to  full  depth 
is  required  for  delivery,  the  canal  will  be  under  its  full  strain  in 
the  first  year  of  use.  Where  checks  are  available,  however,  the 
canal  can  be  primed  by  sections,  holding  water  above  each  check 
in. turn.  This  reduces  the  rate  of  flow  and  the  volume  of  water 
which  may  cause  damage  in  case  breaks  occur. 

For  old  canals,  water  should  be  turned  in  from  2  to  4  weeks 
before  delivery  will  be  required.  If  2  weeks  are  desired  in  which 


GENERAL  MAINTENANCE  7 

to  bring  a  canal  to  full  depth,  priming  should  be  started  4  weeks 
before  water  is  needed  in  sufficient  amounts  so  that  an  interrup- 
tion in  service  will  be  serious.  This  allows  time  for  repairs  should 
need  for  them  develop  during  the  priming.  Where  there  may 
still  be  frost  in  the  banks,  the  running  of  early  water  helps  to  thaw 
the  banks  and  the  longer  period  before  operation  allows  more  time 
for  any  frost  heaving  to  settle.  Running  a  small  flow  in  priming 
also  enables  the  weeds  and  other  drift  which  have  accumulated  to 
be  carried  through  or  collected  at  checks  with  less  damage  from 
clogging  than  would  be  the  case  if  the  water  was  held  high  for 
delivery. 

Shutting  water  out  of  a  canal  too  suddenly  may  be  as  harmful 
as  filling  too  quickly.  In  some  soils  the  sudden  shutting  out  of 
water  due  to  a  break  may  cause  more  actual  damage  than  the 
break  itself.  When  the  canal  is  running  at  full  depth,  the  canal 
banks  absorb  water  until  a  portion  of  the  bank  adjacent  to  the 
water  becomes  saturated.  The  position  of  the  plane  of  saturation 
depends  on  the  conditions  for  escape  of  the  water  as  well  as  its 
absorption.  The  plane  of  saturation  is  held  at  the  water  surface 
at  the  inner  side  of  the  canal  bank.  The  sudden  lowering  of  the 
water  in  the  canal  removes  the  pressure  of  the  water  and  the  inner 
face  of  the  bank  may  slip  if  its  slope  is  steeper  than  can  be  held  by 
the  material  in  its  saturated  condition.  With  light  soils  the 
moisture  in  the  banks  may  drain  out  before  such  slipping  or 
sloughing  has  time  to  occur.  Sloughing  may  also  occur  where 
riprap  or  brush  lining  has  been  used,  the  lining  being  forced  out  of 
position.  Usually,  however,  the  freedom  of  drainage  through 
such  porous  linings  will  prevent  their  injury.  Concrete  lining 
may  be  forced  out  of  position  if  the  drainage  from  the  bank 
is  restricted  so  that  pressure  accumulates  behind  the  lining. 
Sloughing  of  unprotected  canal  banks  is  more  usual  in  heavy  soils 
and  in  canals  operating  under  relatively  high  velocities.  In  such 
canals  the  banks  are  usually  more  nearly  vertical  and  less  pressure 
is  required  to  cause  slipping.  Sandier  soils  require  flatter  side 
slopes  which  combined  with  their  more  rapid  drainage  renders 
them  less  liable  to  such  injury. 

When  breaks  which  may  occur  during  the  period  of  maximum 
demand  for  water  are  repaired,  it  is  usually  necessary  to  bring  the 
canal  back  to  full  discharge  as  quickly  as  possible.  This  may 
cause  additional  erosion  which  might  be  prevented  if  more  time 
for  priming  was  available.  Such  conditions  are  found  where  the 


8  IRRIGATION  SYSTEMS 

operating  velocities  approach  those  which  cause  erosion  in  the 
material  composing  the  canal  banks. 

Canals  in  Unstable  Formations. — Where  canals  are  located  on 
side  hills  or  other  unstable  ground,  more  or  less  difficulty  from 
settling  or  slipping  of  the  banks  or  of  the  whole  canal  is  to  be  ex- 
pected. Such  difficulties  are  usually  of  two  general  kinds:  (1) 
where  the  canal  is  excavated  on  talus  slopes  below  higher  ground 
and  destroys  the  natural  balance  which  has  existed,  the  formation 
may  move,  whether  water  is  in  the  canal  or  not ;  and  (2)  where 
the  seepage  from  the  canal  reaches  uncompacted  material  which 
settles  under  the  influence  of  such  seepage  water.  Various  com- 
binations of  these  two  conditions  may  occur. 

The  first  condition  occurs  where  a  diversion  canal  is  climbing 
from  the  stream  to  bench  land  and  passes  for  part  of  its  length 
through  the  sloping  side  hill.  Such  side  hills  may  consist  of 
material  weathered  from  the  bench  formations.  If  such  upper 
formations  consist  of  shales,  the  slopes  will  contain  clayey  material 
and  usually  exist  under  approximately  the  angle  of  repose  of  the 
material.  To  cut  into  the  slope  to  form  a  canal  section  destroys 
the  footing  of  the  higher  slope.  The  upper  material  may.  slip, 
either  gradually  or  in  larger  movements,  crowding  in  the 
upper  side  of  the  canal  or  pushing  the  foot  of  the  slope  out 
and  carrying  the  canal  with  it.  Such  movements  may  be 
independent  of  any  canal  seepage  being  caused  by  pressure  from 
above  the  canal  rather  than  conditions  below.  Their  occurrence 
is  liable  to  open  cracks  in  the  lower  canal  banks  through  which 
seepage  may  start.  Cases  have  been  observed  where  such  move- 
ments have  taken  place  without  any  evidence  of  seepage  on  the 
slope  below  the  ditch.  The  slipping  of  the  upper  slope  varies 
with  its  moisture  condition  and  may  be  more  marked  at  certain 
seasons.  Such  movements  are  hard  to  restrain  and  usually  con- 
tinue until  the  natural  balance  is  restored.  The  angle  of  sur- 
charge is  large  and  the  footing  unstable,  so  that  retaining  walls  are 
not  practicable.  In  very  steep  slopes  it  may  be  preferable  to  con- 
struct the  canal  as  a  bench  flume  in  order  to  reduce  the  amount  of 
disturbance  of  the  natural  slope.  In  maintaining  canals  in  such 
ground,  the  more  usual  practice  is  to  meet  conditions  as  they  arise 
rather  than  to  attempt  preventive  measures.  Wasteways  should 
be  available  in  such  locations  so  that  the  water  can  be  turned  out 
quickly  and  the  damage  caused  by  breaks  limited  in  amount. 
The  movement  takes  place  gradually  in  many  cases  and  gives 


GENERAL  MAINTENANCE  9 

opportunity  for  the  exercise  of  much  judgment  as  to  how  far  it 
can  be  permitted  to  proceed  without  requiring  shutting  out  the 
water.  When  the  movement  from  above  is  into  the  canal  reduc- 
ing its  cross-sectional  area,  the  material  removed  should  be  placed 
as  a  blanket  on  the  lower  bank  rather  than  as  an  additional  crown 
on  the  bank.  Such  a  blanket  being  in  the  line  of  seepage  will 
add  to  the  safety  of  the  canal.  An  additional  height  of  bank  does 
not  reduce  seepage  and  increases  th  weight  of  the  bank  and  the 
danger  of  its  slipping.  Where  the  formations  occur  in  strata  and 
the  movements  consist  of  the  slipping  of  one  stratum  over  another 
rather  than  as  a  general  bulging,  piling  may  be  effective.  Such 
piling  acts  to  bind  the  strata  together  and  has  been  used  in  some 
cases  with  good  results  on  the  Lower  Yellowstone  project. 

Where  the  seepage  from  the  canal  softens  the  material  on  the 
lower  slopes  so  that  sloughing  may  occur,  treatment  of  the  canal 
to  reduce  seepage  losses  can  be  used. 

These  conditions  of  side-hill  slopes  composed  of  shaly  material 
are  found  in  many  localities  in  the  Great  Plains  areas  east  of  the 
Rocky  Mountains.  The  canal  of  the  Billings  Land  &  Irrigation 
Co.  is  located  in  such  formations  for  a  portion  of  its  length.  In  10 
years  there  have  been  three  breaks  in  a  length  of  ^  mile  and  it 
has  been  necessary  to  shut  water  off  during  the  irrigation  season 
at  other  times  in  order  to  make  repairs.  There  is  no  marked 
seepage  visible  on  the  lower  slope,  the  movement  is  largely  from 
above  the  canal  due  to  the  disturbance  of  its  balance  by  the  ex- 
cavation of  the  canal.  This  slope  has  a  rather  limited  extent  so 
that  it  is  probable  that  the  canal  will  eventually  cease  to  give 
trouble. 

In  some  cases  canals  pass  through  or  over  uncompacted  ma- 
terials such  as  sand  and  gravel.  Seepage  from  the  canal  may 
cause  a  rearrangement  of  the  particles  in  such  material  so  that  a 
smaller  space  is  occupied  and  settlement  occurs.  Such  settle- 
ment may  occur  without  the  removal  of  any  of  such  underlying 
material  by  seepage.  An  instance  is  reported  in  Colorado  where 
a  canal  crossing  a  deposit  of  boulders  and  gravel  mixed  with  clay 
settled  evenly  through  a  height  of  8  inches.  Where  canals  in  fill 
cross  material  containing  much  organic  matter,  such  as  peats,  or 
where  the  underlying  material  is  in  a  semiliquid  condition,  the 
weight  of  the  fill  may  cause  settlement  due  to  compression  of  the 
lower  material.  Where  water  occurs,  the  settlement  may  be 
accompanied  by  a  raising  of  adjacent  lands.  For  such  con- 


10  IRRIGATION  SYSTEMS 

ditions  flat  slopes  on  the  banks,  such  as  4  to  1,  or  even  blank- 
eting of  adjacent  areas,  may  be  required. 

In  side  hills  of  coarse  material,  such  as  talus  slopes  of  coarse 
gravel  or  sand,  visible  seepage  may  occur  without  immediate 
danger.  If  the  seepage  water  is  clear,  indicating  that  underlying 
material  is  not  being  removed,  it  may  be  safe  to  leave  repairs  un- 
til after  the  end  of  the  operation  season.  This  may  be  done  with 
less  danger  on  old  canals  than  on  new,  as  settlement  is  less  liable 
to  occur  in  such  cases.  Where  the  velocity  is  not  high,  the 
source  of  such  seepage  may  be  traced  to  the  canal  and  the  areas 
blanketed  with  finer  material  deposited  while  water  is  in  the 
canal,  more  permanent  repairs  being  made  at  the  end  of  the 
operating  season. 

Canals  through  gypsum  formations  require  great  care  in  opera- 
tion as  such  material  softens  when  wet  so  that  it  has  little  strength 
as  a  bank.  Concrete  lining  may  be  used  to  prevent  seepage  and 
the  saturation  of  the  banks.  On  the  Carlsbad  project  a  canal 
even  when  lined  gave  trouble  due  to  softening  of  the  backfill  by 
the  seepage  through  the  joints  in  the  lining. 

In  repairing  breaks  in  side-hill  canals  it  is  not  usually  desirable 
to  rebuild  on  the  same  alignment.  The  canal  should  be  thrown 
into  the  hill  sufficiently  far  to  give  new  footing.  If  the  hill  is  too 
steep  for  such  relocation,  a  flume  should  be  built  over  the  eroded 
section. 

Overtopping  Canal  Banks. — Breaks  directly  due  to  the  over- 
topping of  canal  banks  are  not  usual.  With  the  amount  of 
freeboard  which  is  ordinarily  used,  a  break  will  generally  occur 
at  some  point  of  weakness  in  the  bank  before  actual  overtopping 
takes  place.  Such  overtopping  is  usually  caused  by  the  choking 
of  the  canal  due  to  the  clogging  of  checks  or  the  slipping  of  ma- 
terial into  the  canal  from  the  upper  slope.  Where  canals  are 
operated  under  checks,  the  turning  back  of  water  by  users  may 
overload  the  canal  unless  ample  wasteways  are  available.  Where 
such  conditions  occur,  much  closer  control  of  the  delivery  of  water 
is  required.  Some  canals  pick  up  cross-drainage  and  this  may 
overload  the  canal  where  summer  rains  occur. 

The  amount  of  freeboard  used  varies  in  good  soils  with  the  size 
of  the  canal :  for  large  and  deep  canals  as  much  as  3  feet  may  be 
used;  for  laterals  of  from  50  to  100  second-feet  capacity  from  1^ 
to  2  feet  and  for  less  than  50  second-feet  capacity  1  foot  would  be 
usual  amounts.  Where  the  flow  in  the  canals  is  closely  regulated, 


GENERAL  MAINTENANCE  11 

smaller  amounts  may  be  needed.  The  amount  needed  also  de- 
pends on  the  top  width  of  the  bank,  being  less  for  wide  banks. 
The  freeboard  required  varies  with  the  character  of  the  material 
in  the  canal  banks.  In  sandy  soils  as  much  as  2  or  3  feet  free- 
board may  be  used  on  small  canals;  in  heavy  soils  as  little  as  1 
foot  may  be  used  on  canals  carrying  200  to  300  second-feet. 

Protection  Against  Canal  Erosion. — Where  the  required  fall 
can  be  secured,  it  is  desirable  that  the  velocity  in  canals  should 
approach  the  allowable  maximum  for  the  material  encountered. 
In  the  adjustment  of  flow  which  always  occurs  between  different 
sections  this  may  result  in  excessive  velocities  in  some  portions. 
The  outside  of  curves  may  be  eroded  or  short  lengths  of  less 
resistant  material  may  be  subject  to  scour.  The  erosion  at 
structures  is  discussed  in  Chapter  II. 

Erosion  can  be  controlled  by  the  use  of  linings  of  concrete,  rock 
or  gravel  or  brush  riprap.  Checks  may  be  used  to  reduce  the 
velocity  below  that  which  causes  erosion;  such  methods  require 
larger  canals  for  the  same  capacity,  however.  Concrete  or  plaster 
lining  will  withstand  relatively  high  velocities.  If  its  use  is  con- 
templated it  is  better  to  include  it  in  the  original  construction  and 
thus  secure  the  advantage  of  the  smaller  cross-section  which  its 
lower  friction  factor  permits.  While  the  cost  of  concrete  lining 
is  higher  than  that  of  other  methods,  the  reduction  in  seepage  loss 
and  cost  of  maintenance,  if  given  proper  value  in  comparisons, 
may  make  such  linings  relatively  cheaper  than  other  forms.  In 
some  cases  wood  linings  have  been  used.  Such  use  is  not  at 
present  usual  due  to  the  relatively  increasing  price  of  lumber  and 
its  shorter  life. 

Gravel  lining  or  blanketing  is  used  to  cover  the  more  easily 
eroded  soils.  Where  the  erosion  is  due  to  wave  action  or  to  high 
velocities  below  structures,  the  larger  fragments  of  rock  riprap 
either  hand-laid  or  loose  are  preferable.  Where  the  velocity  does 
not  materially  exceed  that  which  causes  soil  erosion,  gravel  may 
be  sufficiently  heavy  to  protect  the  canal.  Its  use  requires  a 
location  where  it  can  be  secured  at  relatively  short  hauls.  On 
the  Sunnyside  canal  in  Washington  a  gravel  lining  3  inches  thick 
has  been  used.  The  banks  are  given  a  slope  of  1  on  1%  and  the 
gravel  spread  down  from  the  top  of  the  bank  by  hand.  The 
total  labor  cost  of  spreading  including  superintendence  was  28.6 
cents  per  cubic  yard,  from  10  to  15  cubic  yards  being  spread  per 
man-day.  The  gravel  cost  $1.35  per  cubic  yard  delivered.  For 


12  IRRIGATION  SYSTEMS 

a  3-inch  thickness,  these  figures  are  equivalent  to  a  total  cost  of 
about  1^4  cents  per  square  foot.  It  has  been  found  that  where 
such  gravel  lining  has  been  used  on  curves  there  is  a  tendency  for 
the  silt  to  deposit  in  the  gravel  and  also  for  the  silt  bar  which 
usually  forms  on  the  inside  of  such  curves  to  be  less  noticeable. 
On  the  North  Platte  project  a  gravel  coat  4  inches  thick  has 
been  used  to  protect  canal  banks  from  blowing  where  gravel  could 
be  secured  at  hauls  of  not  over  1J^  miles.  The  cost  of  7  miles  of 
such  protection  was  82  cents  per  cubic  yard  or  1  cent  per  square 
foot. 

Brush  riprap  is  frequently  used  to  prevent  erosion  of  canals  as 
well  as  to  prevent  cutting  around  structures.  Such  linings  are 
often  an  inexpensive  means  of  protection,  particularly  where  wil- 
lows are  available  or  where  sage  brush  can  be  secured  adjacent  to 
the  canal  line.  While  such  methods  are  rather  temporary  in 
character,  the  brush  may  last  several  years,  particularly  if  partly 
buried.  On  the  Sunnyside  project,  sage  brush  and  willow  riprap 
had  to  be  replaced  after  3  or  4  years  use  in  locations  where  no  silt 
was  deposited  in  the  brush.  Greasewood  or  arrow-weed  are  used 
in  some  localities,  although  the  latter  is  more  temporary  than 
other  forms  of  brush. 

Sage  brush  riprap  has  been  extensively  used  on  the  Minidoka 
project  (Plate  I,  Figs.  A  and  B).  On  some  canals  where  erosion 
occurred,  the  brush  was  plowed  in,  being  set  in  each  furrow  and 
covered  by  opening  the  adjacent  furrow.  This  type  of  protec- 
tion costs  about  13  cents  per  square  yard  and  can  be  placed  only 
where  water  is  turned  out  of  the  canal.  When  protection  is  re- 
quired during  the  operation  season  the  sage  brush  can  be  bound 
into  bundles  and  fastened  to  a  continuous  wire  which  is  held  in 
places  by  stakes.  This  method  was  used  near  the  water  surface 
to  prevent  erosion  from  either  scour  or  wave  action,  the  cost  being 
25  cents  per  rod.  In  order  to  provide  a  rough  surface  into  which 
silt  might  settle  and  be  held,  both  sides  of  a  portion  of  the  main 
canal  were  riprapped  with  sage  brush.  The  brush  was  spread  in  a 
heavy  layer  and  held  in  place  with  ordinary  chicken-wire  netting. 
The  netting  was  held  by  2  X  4  strips  fastened  to  3  X  3  posts  driven 
into  the  slope  in  rows  10  feet  apart.  The  average  cost  was  28 
cents  per  square  yard  for  40,000  square  yards.  The  sage  brush 
was  cut  on  adjacent  land  above  the  canal  at  a  cost  of  $1.50  per 
hay-rack  load,  one  load  making  30  square  yards  of  riprap.  Both 
machine  and  hand  driving  were  used  for  the  3X3  posts,  hand 


PLATE  I. 


FIG.  A. — Eroded  bank  in  sandy  soil  before  lining,  Main  canal,  Minidoka 

project. 


FIG.  B. — Main  canal  Minidoka  project,  lined  with  sage  brush  preparatory 

to  silting. 

(Facing  page  12.) 


PLATE  I. 


FIG.  C. — Brush  riprap  used  in  the  Imperial  Valley. 


FIG.  D. — Willows  used  to  reduce  erosion,  Snow  Lateral,  Billings,  Mont. 


GENERAL  MAINTENANCE  13 

driving  proving  the  cheaper,  although  a  very  light  and  easily 
moved  hammer  was  used.  Such  chicken-wire  netting  may  have  a 
life  of  only  2  to  4  years  and  the  brush  may  be  displaced  unless  silt 
has  settled  around  it  sufficiently  to  hold  it. 

On  small  laterals  in  sandy  soil  brush  or  even  straw  may  be 
plowed  or  disked  into  both  the  canal  bank  and  the  water  section 
to  prevent  blowing  and  erosion.  Part  of  this  will  usually  work 
loose  and  be  carried  down  to  the  checks  or  turnouts,  so  that  much 
care  may  be  needed  to  prevent  checking  the  flow  at  such  structures. 
Sage  brush  riprap  when  used  to  prevent  erosion  should  be  laid 
with  the  roots  upstream  and  laid  similarly  to  shingles  on  a  roof 
beginning  at  the  downstream  side.  Rock,  wire,  or  other  means 
of  holding  will  be  required.  In  sandy  soils  greater  difficulty  in 
holding  such  riprap  is  usually  encountered  unless  it  is  well 
weighted  with  rock  or  fastened  with  wire  (Plate  I,  Figs.  C  and  D) . 

In  protecting  canals  which  have  eroded,  it  is  generally  con- 
sidered preferable  to  trim  the  eroded  section  to  smooth  lines  rather 
than  to  attempt  to  restore  the  original  section,  although  in  some 
cases,  particularly  where  concrete  lining  was  to  be  placed,  the 
original  section  has  been  restored.  The  eroded  section  will  more 
nearly  conform  to  the  natural  section  for  the  actual  conditions  of 
flow  and  will  be  more  easily  maintained.  On  curves  around 
points,  the  material  deposited  on  the  inside  may  be  moved  to  the 
outside  of  the  curve  before  protection  is  placed,  if  the  erosion  has 
reduced  the  outer  banks  to  less  than  desired  size. 

SILT  OR  SEDIMENT  IN   CANALS 

The  depositing  of  sediment  in  canals  may  be  desirable  or  ob- 
jectionable, depending  on  the  extent  to  which  it  occurs.  In 
porous  soils  a  deposit  of  silt  over  the  canal  bed  and  sides  will  be  of 
much  benefit  in  reducing  seepage  losses.  On  a  few  systems  silt 
has  been  artificially  applied  for  this  purpose.  The  extent  of 
seepage  losses  is  discussed  in  several  publications.  The  general 
average  values  found,  expressed  in  cubic  feet  depth  of  loss  per  24 
hours  per  square  foot  of  wetted  area,  are  0.5  for  impervious  soils, 
1.0  for  rather  pervious  soils,  1.5  for  pervious  soils,  and  3.0  or  more 
for  porous  soil.  The  seepage  loss,  when  expressed  in  per  cent,  of 
the  discharge  lost  per  mile  of  canal,  varies  with  the  size  of  the 
section  as  well  as  the  material  of  the  canal  bed.  For  typical  con- 
ditions average  losses  are  shown  in  Fig.  1.  Whether  the  value 


14 


IRRIGATION  SYSTEMS 


of  the  water  that  can  be  saved  by  artificial  silting  will  be  sufficient 
to  warrant  the  expense,  is  a  separate  problem  for  each  system. 
It  depends  on  the  cost  of  silting,  the  value  of  the  water  saved  and 
the  value  of  the  prevention  of  possible  damage  from  the  water- 
logging of  lower  lands  by  such  seepage  waters. 

In  canals  operating  under  checks,  the  deposit  of  silt  will  be 
greater  than  where  the  water  is  carried  at  a  fairly  uniform  velocity 
from  the  headgate  to  the  fields.  In  systems  diverting  from 
streams  carrying  an  excess  amount  of  silt,  the  deposits  may  be  so 
extensive  as  to  seriously  affect  the  canal  capacity.  The  majority 
of  streams  used  for  irrigation  in  the  United  States  do  not  carry 


A  2 


Note: 

The    loss    in   per    cent 
per    mile     is     based     on 
typical  canal  cross-sections 
with  an     average    velocity 
of    two  feet    per  second. 


5  10  15  20 

Discharge  in  Second  Feet 


400  500 

Discharge -in  .Second  Feet 


900 


1000 


FIG.  1. — Average  seepage  losses  in  canals  expressed  in  terms  of  per  cent,  loss 

per  mile  of  canal. 

sufficient  silt  to  give  serious  trouble  in  operation.  For  a  number 
of  systems  in  the  Southwest  the  removal  of  silt  is  the  largest  item 
in  maintenance  cost.  The  Colorado  River  represents  the  extreme 
condition  of  American  practice  for  streams  extensively  used. 

Artificial  Silting. — Artificial  silting  may  be  carried  on  either 
during  the  operation  season  by  running  water  containing  silt  into 
the  canal  and  allowing  it  to  distribute  under  the  influences  of 
general  sedimentation,  or  by  depositing  the  silt  directly  at  the 
location  desired  during  the  non-operating  season.  The  latter 
method  is  more  usual  and  generally  preferable  as  it  is  more 
definite.  The  first  method  may  be  suited  to  those  cases  where  the 


GENERAL  MAINTENANCE  15 

whole  system  is  in  sandy  land  and  may  need  such  silting;  the 
latter  method  can  be  used  for  the  more  usual  conditions  in  which 
only  short  lengths  of  canal  through  porous  soils  require  treatment. 
The  deposit  of  silt,  when  pumped  into  the  canal,  cannot  be  closely 
controlled  as  to  the  location  in  which  it  is  deposited  and  an  excess 
amount  must  be  supplied  in  order  to  secure  a  sufficient  covering 
at  all  points.  Neither  method  will  be  successful  in  canals  where 
the  velocity  is  sufficient  to  erode  the  silt.  Such  silt  will  usually 
resist  higher  velocities  after  it  has  been  deposited  than  those 
required  to  carry  the  silt  when  in  suspension.  Where  the  frost 
action  during  the  winter  is  severe,  the  silt  deposited  during  one 
season  may  become  disintegrated  so  that  it  is  carried  out  by  the 
early  season  operation  of  the  following  year. 

Silt  deposited  in  place  during  the  non-operating  season  is  gen- 
erally known  as  puddle  lining.  On  the  Huntley  project  a  total  of 
20,000  square  yards  of  such  lining  4  inches  thick  has  been  placed  at 
a  cost  of  7.1  cents  per  square  yard.  The  haul  on  the  material 
averaged  1.4  miles.  After  spreading,  a  drag  consisting  of  planks 
spiked  together  with  overlapping  edges  was  run  over  the  surface 
in  order  to  break  the  clods.  The  canal  was  then  filled,  the  water 
being  held  over  the  section  by  checks  for  24  hours,  then  lowered  to 
a  depth  of  12  inches  and  a  harrow  dragged  through  the  canal  four 
times  to  puddle  the  material.  The  seepage  loss  after  puddling 
was  found  to  be  1.2  per  cent,  per  mile.  Puddling  may  also  be 
accomplished  by  dragging  a  heavy  chain  along  the  canal  when  the 
silt  is  wet.  On  the  Sunnyside  project,  such  puddle  linings  have 
been  found  to  give  the  best  results  if  placed  so  that  they  will  have 
an  opportunity  to  dry  out  before  water  is  run  over  them.  Both 
sheep  and  laborers  have  been  used  to  puddle  the  lining.  On  some 
of  the  most  porous  soils,  gunny  sacks  were  spread  over  the  canal 
before  the  puddle  lining  was  applied. 

On  the  canal  of  the  Bitter  Root  Valley  Irrigation  Co.  an  en- 
larged section  was  excavated  in  rock  cuts  which  was  lined  with 
about  6  inches  thickness  of  earth  increased  to  12  inches  on  the 
inside  of  some  of  the  lower  banks.  On  one  of  the  canals  on  the 
Uncompahgre  project  similar  lining  12  inches  thick  was  used  on 
both  the  bottom  and  sides.  On  the  Sunnyside  canal  where  gravel 
was  encountered,  the  excavation  was  extended  from  12  to  18  inches 
outside  the  final  section  and  backfilled  with  surface  soil  or  silt. 

The  main  canal  on  the  Grand  Valley  project,  when  located  in 
shale,  was  excavated  to  a  depth  of  1  foot  below  grade  in  order 


16  IRRIGATION  SYSTEMS 

that  silting  might  occur  and  reduce  seepage  losses  without  re- 
ducing the  canal  capacity.  In  some  cases  in  especially  porous 
shale  the  sides  below  the  high-water  surface  were  taken  out  on  a 
slope  of  %  on  1  but  the  water-surface  width  was  not  changed. 
This  gave  a  triangular  area  of  excess  excavation  which  was  later 
filled  by  crowding  in  good  surface  soil  from  the  top  of  the  slope. 
Part  of  this  was  done  before  water  was  turned  in  and  part  with 
water  in  the  canal.  The  latter  method  was  more  effective  in  that 
the  material  compacted  better  and  more  quickly  and  also  spread 
farther  out  on  the  canal  bottom.  In  shales  which  disintegrate, 
the  canal  was  plowed  and  harrowed  after  the  first  season's  use  and 
the  shale  left  exposed  during  the  winter.  In  the  spring  it  was 
again  harrowed  and  rolled  with  a  roller  having  3-inch  projections, 
spaced  6  inches  apart. 

Silting  by  pumping  into  the  canal  during  the  operation  season 
has  been  extensively  tried  on  the  Minidoka  project,  where  on  the 
upper  portion  of  the  gravity  unit  the  canal  is  located  in  sandy  soil 
which  does  not  form  very  stable  banks  and  which  is  subject  to 
considerable  seepage  loss.  A  portion  of  the  main  canal  was 
restored  to  its  original  cross-section  and  the  sides  lined  with  sage 
brush.  The  purpose  of  such  lining  was  to  maintain  the  cross- 
section  and  to  retain  the  silt  when  deposited  in  the  brush.  Silt 
was  pumped  into  the  canal  at  various  times  during  1914  and  1915. 
The  seepage  loss  was  reduced  and  the  safety  of  operation  in- 
creased. Excess  silt  was  deposited  in  the  adjacent  laterals,  in 
sufficient  amounts  to  require  removal  in  some  cases.  This  silting 
has  not  be.en  in  use  sufficiently  long  to  test  its  permanence; 
during  the  period  of  maximum  discharge  there  appears  to  be  some 
tendency  for  the  silt  to  be  picked  up  by  the  water. 

Removal  of  Excess  Silt. — The  methods  of  handling  silt  which 
is  deposited  in  canals  from  the  water  diverted  from  the  streams 
depend  most  largely  on  the  rate  at  which  such  deposits  occur. 
Where  the  rate  of  deposit  is  low  and  there  is  some  margin  of 
capacity  available  in  the  canal,  the  silt  may  be  allowed  to  collect 
until  it  is  sufficient  in  amount  to  make  its  removal  by  teams 
economical.  The  cutting  of  runways  and  other  fixed  charges  are 
then  distributed  over  a  larger  yardage.  In  systems  operating 
under  checks,  the  silt  deposits  above  the  checks  may  be  sluiced 
out  at  seasons  when  checking  for  delivery  is  not  required.  Stir- 
ring or  loosening  the  silt  with  harrows  during  such  sluicing  may 
increase  the  amount  removed.  To  be  successful  such  sluicing 


PLATE  II. 


FIG.  A. — Silting  above  checks,  Imperial  Valley. 


FIG.  B. — Canal  "V"  used  to  remove  silt,  Imperial  Valley. 

(Facing  page  16.) 


PLATE  II. 


FIG.  C. — Canal  in  Imperial  Valley  shortly  after  cleaning,  value  of  n 

0.022. 


FIG.  D. — Similar  canal  to  that  shown  in  Fig.  C  with  excessive  growth  of 
vegetation,  value  of  n  =  0.029  (Figs.  C  and  D  from  Bull.  194,  U.  S.  Dept. 
of  Agric.) 


GENERAL  MAINTENANCE  17 

requires  water  relatively  free  from  silt  when  it  enters  the  canal. 
With  silt-laden  water  but  little  additional  silt  can  be  carried  un- 
less the  velocity  is  increased. 

Silt  can  be  more  economically  removed  by  teams  from  small 
canals  so  that  it  may  be  preferable  to  use  higher  velocities  in  the 
larger  canals  if  sufficient  fall  is  not  available  to  carry  the  silt 
through  to  the  fields.  Enlarged  cross-sections  may  be  used  at 
selected  locations  from  which  the  silt  can  be  more  easily  removed. 
This  may  be  accomplished  by  leaving  the  canal  bottom  below 
grade  in  fills.  The  removal  of  such  deposits  strengthens  the 
banks  in  the  fill.  If  the  silt  is  -coarse  or  sandy,  placing  it  on  the 
slopes  of  the  fill  may  prevent  damage  from  burrowing  animals. 

For  systems  handling  water  carrying  much  silt,  the  design  of  the 
headworks  and  canals  must  be  such  that  the  minimum  amount 
of  silt  will  be  taken  into  the  canal  system  and  that  as  much 
as  possible  carried  through  to  the  fields  or  deposited  in  selected 
locations  along  the  canal  where  it  can  be  more  easily  handled. 
On  the  Williston  project  which  pumps  from  the  Missouri  River, 
settling  basins  are  used  in  which  silt  equal  in  volume  to  from  0.15 
to  0.20  per  cent,  of  the  volume  of  the  water  has  been  removed. 
Such  basins  are  particularly  adapted  to  small  canal  systems. 
On  the  main  canal  supplying  the  Imperial  Valley  large  dredges 
are  used  to  keep  the  canal  below  the  headgates  clear.  Much 
additional  silt  has  to  be  removed  in  the  smaller  canals. 

On  the  smaller  canals  in  the  Imperial  Valley  a  number  of 
methods  of  removing  silt  are  used.  Crowding  with  V-shaped 
drags  or  V'ing  as  it  is  called  is  extensively  employed,  the  V  being 
drawn  through  the  canals  with  tractors  (Plate  II,  Figs.  A  and  B). 
These  serve  to  partially  clean  the  original  canal  section  and  also 
raise  the  canal  banks  so  that  greater  depths  can  be  carried. 
Small  clam-shell  dredges  built  to  be  self-propelling  and  to  travel 
on  the  canal  bank  are  also  used.  In  some  cases  new  canals 
parallel  to  the  old  ones  have  been  built.  As  the  canals  are  oper- 
ated throughout  the  year,  removal  with  teams  is  not  practical. 

The  costs  of  these  different  methods  have  been  as  follows: 
Canal  V'ing  costs  for  1912-1915  are  given  in  Table  II.  In  1915, 
larger  Vs  with  four  caterpillar  engines  were  used  where  previously 
smaller  Vs  drawn  by  two  engines  had  been  employed.  There  are 
335  miles  of  canal  in  this  system,  more  than  one  cleaning  per  year 
•being  required.  V'ing  is  also  being  used  on  the  Yuma  project 
with  satisfactory  results  both  as  to  quality  and  cost. 


18  IRRIGATION  SYSTEMS 

TABLE  II. — COST  OF  CANAL  VING — IMPERIAL  WATER  Co.  No.  1 


1912 

1913 

1914 

1915 

Number  miles  of  ditch  Vd  

481 

431 

448 

361 

Cost  per  mile  for  V'ing  

$17.05 

$21  99 

$22  64 

$28  02 

Cost  per  mile  repairs  to  engine  

13  43 

14  31 

16  29 

16  40 

Cost  per  mile  repairs  to  Vs 

3  93 

2  38 

0  93 

7  13 

Cost  per  mile  fuel  and  oil  

6.52 

6  69 

6  64 

8  05 

Cost  per  mile  of  Mexican  labor  following  V 

13.42 

16.04 

21.07 

21.64 

Total  average  cost  per  mile  

$54.35 

$61.41 

$67.57 

$81.24 

During  1915,  two  portable  clam-shell  dredges  moved  255,000 
cubic  yards  at  a  cost  of  9.2  cents  per  cubic  yard.  They  travelled 
83  miles  in  going  from  one  canal  to  another  at  a  cost  of  $6.72  per 
mile.  The  repairs  cost  $349  per  dredge  per  year  as  compared 
with  an  average  cost  of  $1,480  per  year  for  repairs  on  one  cater- 
pillar engine  used  in  V'ing.  Where  joint  grass  grows  at  the  edges 
of  the  canal,  the  dredges  are  able  to  remove  such  growth  much 
better  than  other  forms  of  equipment.  Disk  and  grader  outfits, 
used  on  canal  banks  after  dredging  to  widen  the  bank,  make 
roads  and  discourage  growth,  cost  $20.40  per  mile  in  1915,  307 
miles  being  covered. 

Similar  difficulties  with  silt  have  been  experienced  on  the 
Yuma  project  of  the  U.  S.  Reclamation  Service.  A  year's  run 
of  water  causes  a  deposit  of  silt  in  the  ditches  from  6  to  12  inches 
in  depth  as  well  as  a  layer  on  the  sides  and  requires  annual  clean- 
ing. Formerly  cleaning  by  team  and  by  hand  was  used ;  a  V  is 
now  used,  being  hauled  by  a  tractor  which  pushes  the  mud  out- 
ward to  the  top  leaving  slopes  of  about  1  on  1)^.  A  trip  through 
the  ditch  for  each  side  is  made.  In  1915,  50  miles  of  canal  were 
cleaned  by  teams  and  hand  at  an  average  cost  of  $579  per  mile. 
In  May,  1916,  12  miles  of  canal  were  cleaned  with  the  V  at  a 
cost  of  $55  a  mile,  better  results  being  secured.  Dredging  with 
drag-line  excavators  is  used  on  the  larger  canals,  the  cost  being 
from  3  to  8  cents  per  cubic  yard,  including  all  costs. 

In  cleaning  main  laterals  on  the  Turlock  Irrigation  District, 
lengths  of  from  1  to  6  miles  are  worked  over  completely,  adjoin- 
ing sections  being  cleaned  in  other  years,  no  patchwork  being 
done.  The  berms  formed  by  silt  are  covered  with  water  grass 
which  is  difficult  to  plow.  Cleaning  to  a  20-foot  bottom  width 


GENERAL  MAINTENANCE  19 

with  2  to  1  slopes  costs  from  $250  to  $500  per  mile,  depending  on 
the  extent  of  the  cleaning  required. 

AQUATIC  GROWTHS 

This  term  is  used  to  cover  all  types  of  growth  which  occur 
within  the  water  cross-section  of  canals.  Plants  which  have  their 
roots  in  the  soil  above  the  water  and  trail  over  into  the  canal  are 
discussed  with  other  vegetation  on  canal  banks. 

Aquatic  growths  in  irrigation  canals  include  a  large  number  of 
different  plants.  In  addition  to  the  actual  differences  in  the 
plants  themselves,  there  is  much  confusion  in  regard  to  the  names 
by  which  the  plants  are  known.  In  some  localities  the  term  moss 
is  used  to  cover  a  number  of  different  plants,  none  or  few  of  which 
may  be  mosses  as  these  are  botanically  denned.  In  other  sections 
the  general  term  algae  is  used  for  growths  having  no  relation  to 
the  true  algae.  While  the  use  of  correct  botanical  terms  may 
not  be  essential,  if  the  common  terms  used  are  consistently  applied, 
where  there  is  so  much  confusion  in  regard  to  the  terms  used  it  is 
desirable  to  at  least  understand  the  character  of  plants  coming 
within  the  general  classifications. 

Kinds  of  Aquatic  Growths. — The  type  of  growth  generally  re- 
ferred to  as  canal  moss  is  not  a  true  moss.  The  plants  of  most 
general  occurrence  belong  to  the  class  known  botanically  as 
Potamogetoh  or  pond-weeds.  The  pond-weeds  are  perennial 
herbs.  The  flowers  develop  fruiting  bodies  in  the  form  of  small 
rounded  nutlets.  The  most  common  variety  of  this  is  known  hi 
some  sections  as  horsetail  moss,  due  to  its  appearance  in  the 
water.  These  plants  have  their  roots  in  the  sides  and  bottom  of 
the  canal,  the  growth  trailing  downstream  under  the  action  of  the 
current.  A  single  plant  has  sufficient  branches  to  form  a  cluster 
about  the  size  of  a  horse's  tail  and  may  grow  to  a  length  of  6  feet 
or  more.  These  pond-weeds  produce  flowers  at  the  base  of  the 
branches;  such  flowers,  however,  do  not  appear  until  the  plant 
approaches  maturity.  The  flowers  are  followed  by  the  seeds  by 
which  the  pond-weed  propagates  itself.  The  method  of  removing 
this  plant  is  affected  by  its  habit  of  growth,  before  flowering  the 
stalk  is  tougher  and  less  easily  broken  than  when  nearer  maturity. 
Chains  or  other  means  of  breaking  the  plant  are  not  usually 
successful  in  the  earlier  stages  of  growth,  some  means  of  cutting 
rather  than  breaking  being  required. 


20  IRRIGATION  SYSTEMS 

This  pond-weed  or  "moss"  occurs  very  irregularly.  New 
systems  may  be  free  from  it  for  some  years;  it  may  then  appear 
over  the  whole  system  in  a  single  year.  Its  growth  is  usually 
greatest  in  the  laterals  or  shallow  canals,  due  probably  to  the 
effect  of  light.  In  deeper  sections,  particularly  where  the  water 
contains  silt,  less  trouble  is  experienced.  It  has  also  been  found 
that  the  growth  in  darkened  areas  under  bridges  or  in  tunnels  will 
be  small  or  entirely  absent.  Its  growth  is  also  affected  by  tem- 
perature conditions  and  is  most  rapid  in  the  months  of  higher 
water  temperature.  These  are  also  the  months  of  maximum 
demand  for  water,  so  that  such  plants  make  it  doubly  hard  to 
meet  the  peak  demand.  The  growth  may  very  materially  re- 
duce the  capacity  of  the  canal.  This  makes  it  necessary  to  reduce 
the  discharge,  increase  the  depth  carried  or  clean  the  canal  by 
removing  the  vegetation.  The  amount  of  reduction  in  discharge 
or  increase  in  depth  which  can  be  made  is  generally  relatively 
limited,  and  removal  of  the  growth  is  the  usual  remedy.  The 
rate  of  growth  may  be  as  much  as  4  to  6  inches  in  length  per  day 
and  may  increase  the  depth  of  water  in  a  canal  with  a  constant 
discharge  as  much  as  0.1  or  0.2  foot  per  day.  The  total  reduction 
in  carrying  capacity  at  a  given  stage  may  amount  to  over  50 
per  cent,  of  the  normal.  From  one  to  three  and  occasionally 
four  cuttings  or  other  means  of  removal  per  season  may  be  re- 
quired depending  on  local  conditions.  A  number  of  means  of 
treatment  have  been  developed  adapted  to  the  varying  local 
conditions. 

The  water  buttercup  is  another  plant  which  is  common  in 
ditches  and  ponds  in  the  coast  States;  it  occurs  less  frequently 
in  running  water.  This  is  a  perennial  which  has  its  leaves  sub- 
mersed and  which  has  yellowish  flowers  about  J4  inch  or  less  in 
diameter.  It  is  similar  to  the  pond-weeds  in  its  action  in  retard- 
ing flow.  In  some  localities  the  buttercup  may  mature  and 
break  naturally  in  September,  giving  a  clean  channel  in  the  later 
operation  season. 

The  fine  growth  called  frog  moss  is  a  water  moss.  This  pro- 
duces no  flowers  but  is  spread  by  fragmentation.  The  so-called 
black  grass  is  similar  in  nature. 

Algae  are  cellular  growths  which  occur  in  stagnant  water  or 
attached  to  other  growths.  They  are  devoid  of  differentiation 
into  root,  stem  and  leaf.  By  virtue  of  the  possession  of  chloro- 
phyll, all  algse  are  capable  of  utilizing  carbonic  acid  gas  as  a 


GENERAL  MAINTENANCE  21 

source  of  carbon  in  the  presence  of  sunlight.  Algae  are  a  source 
of  pollution  of  municipal  supplies  and  have  been  closely  studied 
in  this  relation  in  the  East.  The  actual  algae  found  in  irrigation 
canals  are  of  much  less  importance  or  harm  than  the  other 
growths  to  which  they  are  attached. 

Lichens  may  occur  in  some  cases  although  very  few  lichens  are 
normally  and  probably  none  are  entirely  aquatic.  Lichens  are 
flowerless  plants  composed  of  loose,  cellular  tissue,  a  parasitic 
fungus  and  a  number  of  algal  cells.  Lichens  attach  themselves 
to  other  plants  or  to  earth  or  rock  surfaces. 

The  extent  to  which  such  growths  may  fill  the  canal  section  is 
illustrated  in  Plate  III,  Figs.  A  and  B. 

METHODS  OF  HANDLING  AQUATIC  GROWTHS 

Cutting. — Due  to  the  fact  that  these  plants  trail  downstream 
from  their  place  of  growth,  it  is  possible  to  effectively  remove 
them  by  cutting  with  a  form  of  saw  or  knife  which  is  weighted 
so  as  to  pass  below  the  plant  and  cut  just  above  the  roots.  A 
patented  saw  known  as  the  Ziemsen  Submarine  Weed  Cutting 
Saw,  handled  by  Aschert  Bros.,  Cedar  Lake,  West  Bend,  Wis.,  is 
generally  used.  This  consists  of  a  small  steel  band  with  teeth 
on  both  sides.  Weights  or  sinkers  are  attached  along  the  saw 
and  light  ropes  at  the  ends  for  use  in  handling.  The  list  price 
has  been  $20  for  a  10-yard  length  complete;  the  blade  alone  is 
listed  at  $1.50  per  yard. 

This  saw  is  operated  by  one  man  at  each  end.  Better  results 
are  usually  secured  by  sawing  diagonally  at  about  an  angle  of 
30°  with  the  ditch,  the  forward  man  doing  most  of  the  cutting, 
the  rear  man  only  drawing  the  saw  back.  If  the  two  ends  are 
kept  abreast,  the  center  has  a  greater  tendency  to  run  over  the 
moss  without  cutting.  The  saw,  if  pulled  with  short  quick 
jerks,  will  cut  from  6  to  12  inches  per  stroke.  In  addition  to  the 
men  cutting,  from  one  to  three  men  will  be  needed  on  the  canal 
below  to  remove  the  moss  as  it  floats  down.  This  is  usually  done 
from  bridges,  checks  or  other  structures  from  which  the  men  can 
work.  Where  only  the  pond-weeds  occur  this  saw  will  give  good 
results.  It  can  also  be  used  at  an  earlier  stage  of  growth  than 
chaining.  Where  the  finer  growths  usually  known  as  black  grass 
or  frog  moss  occur  with  the  pond-weed,  frequent  cleaning  of  the 
saw  may  be  required  due  to  the  catching  of  these  finer  growths 


22  IRRIGATION  SYSTEMS 

on  the  saw  teeth.  Two  men  sawing  can  usually  cover  from  Y± 
to  1  mile  of  ditch  per  day.  One-fourth  mile  would  represent 
unusually  heavy  moss  or  unfavorable  conditions  for  working. 
On  the  Minidoka  project  in  1916,  as  many  as  40  men  were  em- 
ployed at  one  time  in  cutting  moss,  the  average  cost  being  $22 
per  mile.  On  the  Orland  project  in  1914  the  cost  per  mile 
cleaned  with  saws  was  $17  for  each  cleaning.  The  saw  was  used 
in  channels  too  deep  to  work  stock.  In  small  laterals  in  which 
men  can  wade,  an  ordinary  brush  scythe  will  give  good  results. 
The  cost  with  scythes  in  laterals  was  $11  per  mile  on  the  Minidoka 
project  in  1916,  the  water  being  lowered  to  depths  of  1  foot  during 
cutting. 

Dragging. — Heavy  chains  with  one  or  two  horses  on  each  end 
are  also  used,  the  chain  being  dragged  upstream  and  breaking 
the  growth  near  the  roots.  This  method  is  most  successful  on 
mature  or  long  pond- weed.  For  the  tougher  earlier  growth  the 
chain  may  run  over  the  growths  without  breaking  it.  A  %-inch 
cable  has  also  been  used.  On  the  Orland  project  a  drag  made  of 
railroad  iron,  somewhat  on  the  plan  of  a  split-log  road  drag,  has 
been  used  on  canals  in  which  the  depth  was  sufficiently  small 
to  permit  the  use  of  horses  in  the  water.  The  cost  in  1914  was 
$12  per  mile  for  each  cleaning.  On  the  Minidoka  project  in  1916, 
the  average  cost  of  chaining  was  $8  per  mile.  Where  the  canal 
has  sufficient  capacity  so  that  removal  may  not  be  required  until 
the  growth  is  fairly  ripe,  some  method  of  dragging  is  more  usual 
than  sawing.  Where  it  can  be  used,  dragging  is  generally  pref- 
erable due  to  its  lower  cost  and  the  greater  speed  obtainable. 

Harrowing. — Harrowing  with  weighted  disk  harrows  has  been 
successfully  used  on  the  Bear  River  canal  in  Utah,  the  Truckee 
Carson  project  in  Nevada  and  on  other  systems.  .  However,  in 
some  cases  where  this  method  has  been  tried  it  has  not  given  good 
results.  The  disks  are  set  nearly  straight  so  that  the  growth  will 
be  cut  but  not  covered,  allowing  the  plants  to  float  downstream 
to  be  removed  as  in  other  methods.  For  depths  up  to  3  feet 
the  team  can  walk  in  the  ditch;  it  is  usually  better,  however,  to 
use  a  team  on  each  bank.  The  disk  harrow  also  appears  to 
injure  the  roots  and  hinder  growth  later  during  the  same  season. 
Spring  tooth  harrows  have  been  used  on  the  Sunnyside  and  Salt 
River  projects.  Harrowing  is  carried  on  without  turning  water 
out  of  the  canals  or  interrupting  the  delivery  of  water.  The 
cost  in  laterals  on  the  Minidoka  project  was  $9  per  mile  in  1916. 


GENERAL  MAINTENANCE  23 

Sun-killing. — Pond-weed  and  other  aquatic  growths  can  be 
killed  by  exposure  to  the  sun  for  periods  of  from  3  to  8  days. 
Where  the  delivery  methods  are  such  that  water  can  be  turned 
out  of  portions  of  the  system,  this  method  is  both  cheap  and 
effective.  Such  conditions  are  found  where  water  is  delivered 
under  rotation  and  the  rotation  is  carried  on  between  laterals  or 
sub-laterals.  Under  delivery-on-demand  or  continuous-flow 
methods  of  operation  it  may  be  possible  to  arrange  to  turn  water 
out  of  sub-laterals  for  a  few  days  in  order  to  control  aquatic 
growth.  On  some  canals,  particularly  those  having  high  ve- 
locities, alternately  turning  the  water  on  and  off  may  cause  slough- 
ing of  the  banks.  Such  turning  out  of  water  is  not  generally  desir- 
able for  laterals  carrying  over  40  or  50  second-feet.  It  is  also 
not  adapted  to  canals  which  do  not  dry  out  quickly,  as  the  time 
required  is  longer  than  water  can  be  shut  out  from  the  ditch. 

Miscellaneous  Methods. — Oiling  of  the  canal  bed  has  been  tried 
in  a  number  of  cases  with  varying  success.  The  principal  objection 
to  the  method  appears  to  be  the  short  time  such  oiling  is  effective 
and  the  relatively  large  expense  in  proportion  to  the  benefit. 

Chemical  treatment,  such  as  the  use  of  copper  sulphate,  has 
also  been  tried.  This  method  has  been  successfully  used  for  the 
control  of  algae  in  municipal  storage  supplies;  in  irrigation  the 
quantities  to  be  treated  are  much  larger  and  the  water  flowing 
in  the  canals  does  not  give  as  favorable  conditions  for  the  use  of 
such  chemicals  as  is  the  case  with  ponded  water.  It  has  been 
tried  in  a  few  instances  with  fair  success  in  some  of  the  smaller 
lined  canals  in  Southern  California. 

On  small  canals,  long-handled  rakes,  operated  from  the  canal 
banks,  may  be  used.  On  the  Wapato  Indian  Reservation  drain- 
age canals,  it  is  stated  that  two  men  clean  about  J£  mile  per  day 
at  a  cost  of  $25  per  mile.  In  one  case  a  cylinder  from  a  threshing 
machine  was  dragged  lengthwise  through  a  drainage  ditch  with 
good  results.  On  the  Buckeye  canal  in  Arizona  it  was  observed 
that  moss  did  not  grow,  where  cattle  watered  in  the  canal,  due  to 
the  trampling  of  the  sides.  Spraying  with  arsenic  solutions  as 
discussed  on  page  29  for  growths  on  canal  banks  might  be  effec- 
tive if  applied  at  the  end  of  the  operating  season  by  destroying 
the  roots  on  perennial  plants  and  the  seeds  on  mature  growths. 
On  the  sub-laterals  of  the  Sacramento  Valley  Irrigation  Co.  an 
oil  burner  for  destroying  weeds  which  grow  in  the  laterals  between 
irrigations  has  been  tried  with  indifferent  success. 


24  IRRIGATION  SYSTEMS 

SEMI-AQUATIC  PLANTS 

In  addition  to  the  growths  entirely  aquatic  in  nature  there  are 
a  number  of  plants  which. have  their  roots  within  the  canal  water 
cross-section,  but  whose  growth  is  largely  above  the  water  sur- 
face. Among  such  plants  are  tules,  cat  tails,  water  grass,  bam- 
boo and  joint  grass.  Other  growths  such  as  Johnson  and  Ber- 
muda grass  may  extend  from  the  adjoining  soil  into  the  water. 
Such  plants  are  more  troublesome  in  the  warmer  climates  than 
in  the  mountain  states,  particularly  in  marshy  areas  at  the  sides 
of  canals  or  in  silt-laden  water.  For  the  portions  of  the  cross- 
section  in  which  they  may  grow,  such  plants  will  more  effectively 
stop  the  flow  than  the  strictly  aquatic  plants.  In  water  carry- 
ing large  amounts  of  silt  all  forms  of  aquatic  vegetation  may 
reduce  the  velocity  in  their  vicinity  so  as  to  cause  local  silt 
deposits.  It  is  particularly  necessary  to  control  vegetation  in 
such  canals.  The  growth  of  the  semi-aquatic  plants  is  limited 
to  the  shallower  depths.  Owing  to  their  erect  growth  they  can 
not  be  broken  off  by  dragging  as  readily  as  the  pond-weeds. 
They  can  usually  be  cut  with  brush  scythes  at  a  cost  of  about  $12 
per  mile.  Plate  II,  Figs.  C  and  D,  illustrates  the  extent  to  which 
such  growth  may  reduce  the  capacity  of  laterals. 

Tules  can  sometimes  be  mowed  from  the  banks  when  they  do 
not  extend  too  far  into  the  canal.  In  the  Imperial  Valley  one 
method  used  has  been  to  destroy  the  tules  before  their  growth 
becomes  thick  by  the  use  of  straight-handled  hoes  called  "tule 
cutters"  operated  from  the  bank,  the  tule  being  cut  at  its  roots. 
This  also  prevents  their  spreading.  On  the  Alta  Irrigation 
district  near  Fresno  a  heavy  chain  drag  is  used.  This  has  been 
found  to  bruise  the  tules  so  that  they  are  killed,  although  they 
are  not  actually  removed  by  the  chain.  On  the  Turlock  Irriga- 
tion district  one  plowing  when  water  is  out  has  been  successful 
in  destroying  tules.  When  the  extent  of  the  growth  is  small, 
they  may  be  dug  out  by  hand  while  the  ditch  is  still  wet. 

Barnyard  millet  or  water  grass  is  an  annual  which  is  very 
troublesome  in  parts  of  California  and  the  Southern  States. 
This  grows  in  water  up  to  12  inches  in  depth  and  is  the  same  grass 
which  causes  damage  in  rice  fields.  It  is  most  troublesome  in 
laterals  of  10  second-feet  or  less  capacity.  Water  grass  will 
sprout  and  seed  in  about  45  days;  when  cut,  a  new  growth  de- 
velops from  the  same  roots.  In  some  cases  it  has  been  pulled 


GENERAL  MAINTENANCE  25 

out;  in  others,  continuous  grazing  has  been  tried.  Sheep  will 
keep  the  growth  down  but  will  not  exterminate  it.  Water  grass 
may  grow  as  much  as  18  inches  per  month. 

VEGETATION  ON  CANAL  BANKS 

The  vegetation  on  canal  banks  varies  from  plants  which  are 
very  desirable  to  those  which  are  very  detrimental.  In  blowing 
soils,  the  growth  of  vegetation  on  the  banks  may  be  very  benefi- 
cial. Many  plants  interfere  with  the  use  of  the  banks,  extend 
into  the  water  and  retard  the  flow,  are  the  source  of  tumbling 
weeds  which  may  be  caught  on  and  clog  screens  or  structures  in 
the  canal,  or  supply  weed  seeds  which  may  foul  fields  on  the 
farms.  The  methods  of  handling  such  vegetation  on  canal 
banks  vary  with  its  character  and  purpose  and  include  grazing, 
mowing,  chemical  treatment  and  seeding  of  desirable  plants. 

Including  both  main  canals  and  laterals,  from  1  to  2  per  cent, 
of  the  total  area  under  a  canal  system  will  usually  be  occupied 
by  canal  rights  of  way.  Of  such  rights  of  way,  one-half  or  more 
will  consist  of  canal  banks  and  adjacent  areas,  the  remainder 
consisting  of  the  actual  canal  section.  The  area  of  canal  banks 
may  amount  to  1  per  cent,  of  the  total  area  under  a  system  or 
the  equivalent  of  several  large  farms  on  canals  serving  relatively 
large  areas. 

Native  Plants. — The  kinds  of  weeds  which  grow  without  culti- 
vation on  canal  banks  vary  with  the  soil  and  climatic  conditions. 
Among  the  more  common  ones,  are  the  tumbling  weeds,  sweet 
clover,  broncho  grass  or  "cheat,"  Johnson  grass,  Bermuda  grass, 
water  grass  or  barnyard  millet,  and  willows. 

Three  kinds  of  tumbling  weeds  are  found  along  canals.  These 
are  Russian  thistle,  tumbling  mustard  and  the  ordinary  tumble 
weed.  These  all  break  off  at  the  ground  when  mature  and 
scatter  their  seed  by  being  rolled  across  country  by  the  wind. 
They  cause  much  trouble  and  expense  in  canal  operation  both 
for  the  collection  and  burning  of  those  blown  into  the  canals  and 
also  from  actual  damage  due  to  the  clogging  of  screens  or  struc- 
tures. Russian  thistle  has  no  marked  stalk,  being  flatly  spherical 
in  shape  and  growing  from  1  to  3  feet  in  diameter.  It  is  not  an 
actual  thistle,  being  properly  a  salt  wort.  It  can  be  distinguished 
from  the  common  tumble  weed  by  its  sharp  spikes.  Russian 
thistle  does  not  usually  mature  and  start  to  move  until  near  the 


26  IRRIGATION  SYSTEMS 

end  of  the  operation  season,  the  trouble  with  this  plant  coming 
mainly  in  the  spring  from  the  growth  of  the  previous  year. 
Tumbling,  or  "Jim  Hill"  mustard,  as  it  is  called  in  the  North- 
west, matures  earlier  in  the  season  and  may  give  trouble  in  some 
localities  during  the  season  of  heavy  demand  for  water  when  the 
available  margin  against  injury  due  to  the  clogging  of  checks  or 
turnouts  is  small.  This  mustard  germinates  in  both  spring  and 
fall  and  grows  from  1  to  4  feet  high.  The  ordinary  tumble  weed 
is  also  found  in  many  parts  of  the  West  but  is  frequently  not 
distinguished  from  the  Russian  thistle. 

The  weeds  which  are  blown  into  canals  during  the  non-opera- 
tion season  are  most  economically  removed  just  before  water  is 
turned  in  the  following  spring.  This  should  not  be  done  too 
far  in  advance  of  running  water  or  a  second  cleaning  may  be 
required.  Such  weeds  are  collected  and- burned.  Weeds  blown 
into  the  canal  during  operation  are  usually  collected  at  structures 
or  screens.  These  require  drying  before  they  can  be  burned  and 
when  removed  from  the  canal  to  dry  require  some  means  of 
preventing  their  being  blown  in  again.  In  some  cases  the  pre- 
vailing winds  may  be  from  one  direction,  such  as  with  the  natural 
drainage  of  the  country,  so  that  the  weeds  may  be  placed  on  the 
leeward  side.  On  some  systems  woven-wire  weed  baskets  are 
used.  These  are  placed  at  structures.  As  the  weeds  are  re- 
moved from  the  canal  they  are  placed  in  the  baskets  until  they 
are  dry  enough  to  be  burned. 

Sweet  clover  frequently  grows  to  a  height  of  several  feet  and 
of  such  thickness  as  to  interfere  with  the  use  of  the  canal  banks 
by  the  canal  rider  (Plate  III,  Fig.  D).  It  also  may  extend  into 
or  droop  down  to  the  water  in  the  canal  and  restrict  the  flow, 
particularly  in  the  smaller  laterals.  If  allowed  to  mature,  the 
stalks  become  woody  and  if  broken  may  get  into  the  canal  and 
cause  trouble  similar  to  that  caused  by  tumble  weeds.  Sweet 
clover  does  not  naturally  travel  in  this  way,  however.  Sweet 
clover  is  supposed  to  be  a  biennial  requiring  2  years  for  its  exter- 
mination even  if  seeding  is  prevented.  It  is  best  handled  by 
mowing.  If  cut  before  blooming,  new  growth  will  start  from  the 
same  roots. 

A  grass  variously  called  needle  grass,  June  grass,  broncho  grass, 
Mormon  oats,  military  grass,  wild  brome,  chess  or  cheat  is  of 
general  occurrence  particularly  in  the  northern  half  of  the  West- 
ern States.  Its  growth  is  not  objectionable  from  the  point  of 


PLATE  III. 


FIG.  A. — Aquatic  vegetation  in  a  canal  in  San  Joaquin  Valley,  California. 


FIG.  B. — Vegetation  at  sides  of  canal,  causing  silt  berms. 

(Facing  page  26.) 


PLATE  III. 


FIG.  C. — Removing  moss  from  a  lined  canal  in  Southern  California. 


FIG.  D. — Sweet  clover  on  canal  banks,  Big  Ditch,  Montana. 


GENERAL  MAINTENANCE  27 

view  of  canal  operation  as  it  does  not  grow  sufficiently  high  to 
interfere  with  the  use  of  the  banks.  Its  seed,  however,  may  be 
carried  into  the  fields  where  the  grass  is  very  injurious  to  the 
first  cutting  of  alfalfa. 

Johnson  grass  obstructs  the  flow  at  the  waters  edge  and  by 
drooping  into  the  canal.  Other  grasses  such  as  joint  grass  are 
similar  in  effect.  Johnson  grass  is  a  particularly  undesirable 
plant  on  canal  banks  as  the  seed  may  be  carried  onto  the  farms. 
Once  established,  its  persistence  and  hardiness  make  it  difficult 
to  eradicate.  Several  states  have  statutes  making  it  unlawful 
to  permit  Johnson  grass  to  go  to  seed.  The  cost  of  cleaning 
canals  of  Johnson  grass  may  be  as  much  as  $200  per  mile.  John- 
son grass  is  propagated  by  both  seeds  and  rootstocks.  Grazing 
with  sheep  is  the  most  effective  means  of  control. 

Bermuda  grass  on  canal  banks  may  not  be  particularly  objec- 
tionable from  the  point  of  view  of  canal  operation  as  its  growth 
is  not  high  and  it  aids  in  holding  the  soil.  On  laterals  operated 
only  part  of  the  time,  it  may  grow  across  the  bottom  and  obstruct 
the  flow.  Bermuda  grass  is  found  only  in  the  South  and  South- 
west, where  winter  temperatures  do  not  kill  the  roots.  It  is  a 
serious  pest  when  established  in  fields  and  its  growth  along 
canals  should  be  limited  in  order  to  prevent  its  spreading.  It 
spreads  by  jointed  rootstocks  and  aerial  runners  as  well  as  by 
seed.  In  humid  climates  the  seed  is  not  fertile;  in  arid  regions 
the  seed  is  fertile  and  is  the  chief  means  of  spreading.  The 
growth  is  most  rapid  in  the  early  fall.  Bermuda  grass  is  resist- 
ant to  alkali,  drouth  and  submergence,  but  will  not  stand  shade. 

Wild  oats,  sunflowers  and  various  grasses  may  give  trouble  in 
different  localities.  These  can  generally  be  controlled  by  mow- 
ing. Arrow-weed  causes  much  trouble  in  localities  of  high  tem- 
perature, frequent  cuttings  being  required  for  its  control. 

Willows  grow  on  many  canal  banks  particularly  where  the 
lower  toe  is  moist  or  in  the  shallow  water  at  the  canal  edge.  The 
silt  which  is  usually  deposited  around  willows  forms  a  berm  which 
reduces  the  canal  capacity.  They  are  more  easily  killed  if  cut 
when  the  sap  flow  is  relatively  rapid  as  in  hot  weather.  Con- 
tinuous cutting  is  generally  required.  Sheep  may  reduce  the 
growth  by  eating  the  leaves.  Other  trees  which  may  occasion- 
ally grow  along  canal  banks  are  usually  more  harmful  than 
beneficial  as  they  interfere  with  the  use  of  the  banks  in  patrolling 
and  in  canal  cleaning.  Brush  along  the  banks  must  be  cut  be- 


28  IRRIGATION  SYSTEMS 

fore  aquatic  growths  can  be  removed  by  sawing  or  dragging. 
Cutting  brush  on  223  miles  of  canal  on  Imperial  Water  Co.  No.  1, 
in  1915,  cost  $34.50  per  mile.  Cutting  willows  cost  $27  per  mile 
of  canal  on  23  miles  on  the  Minidoka  project  in  1916. 

GENERAL  METHODS  OF  CONTROL  OF  VEGETATION  ON  CANAL 

BANKS 

Grazing. — Where  the  vegetation  on  the  canal  bank  is  heavy 
and  of  a  character  which  furnishes  nutritive  grazing,  the  pastur- 
ing of  sheep  has  been  not  only  beneficial  to  the  canal  but  in  some 
cases  directly  profitable.  This  condition  is  found  on  some  sys- 
tems in  the  Southwest  where  Johnson  grass  forms  a  large  part 
of  the  growth.  Sheep  are  used  for  this  purpose  as  they  pack  the 
banks  without  wearing  them  down  as  much  as  cattle,  graze  more 
closely  and  will  themselves  make  some  growth  on  much  leaner 
pasturage  than  other  stock. 

Sheep  may  be  herded  on  the  banks  or  controlled  by  fencing. 
The  latter  method  is  preferable  as  it  reduces  the  cost  of  herding 
and  the  sheep  can  be  confined  more  easily  to  narrow  areas.  This, 
however,  may  require  fencing  canals  where  otherwise  the  expense 
of  fencing  would  not  have  to  be  incurred.  On  the  Orland  pro- 
ject, the  Reclamation  Service  has  in  some  cases  fenced  one  side 
of  canals  where  the  adjoining  land  owner  has  agreed  to  fence  the 
other  and  to  maintain  sheep  on  the  banks.  On  laterals  about 
six  head  per  1,000  feet  of  ditch  have  been  used.  Such  grazing 
of  canals  should  not  be  confused  with  the  trampling  of  banks 
and  sides  of  canals  where  range  stock  are  allowed  access  to  them. 
Grazing  or  the  driving  of  cattle  across  canals  when  not  in  use  is 
generally  harmful  and  should  be  prevented. 

Pasturing  of  sheep  and  goats  has  been  extensively  used  on  the 
Salt  River  project.  This  not  only  reduced  the  expense  of  hand- 
ling Johnson  grass  but  also  nearly  eliminated  the  burrowing 
animals  due  to  the  packing  of  the  banks.  Two  herders  were  used 
to  handle  400  to  500  sheep  which  were  grazed  on  from  50  to  100 
yards  of  bank  at  a  time.  The  use  of  dogs  was  not  practical  as 
there  was  too  much  tendency  to  crowd  the  sheep.  It  was  found 
that  the  sheep  ate  sunflower,  sourdock,  sour  clover,  burr  clover, 
Bermuda  grass,  salt  bush,  and  most  tree  leaves  including  willows, 
but  would  not  eat  tobacco,  thistles,  foxtail  when  headed  out  and 
water  grass  when  large.  Banks  grazed  for  2  years  showed  95 


GENERAL  MAINTENANCE  29 

per  cent,  of  the  Johnson  grass  to  have  been  killed.  In  1914,  40 
miles  of  canals  of  various  sizes  were  grazed,  decreasing  the  main- 
tenance cost  $115  per  mile.  The  sheep  account  showed  a  loss 
of  $1,480  but  the  band  was  improved  during  the  year  by  the 
replacement  of  the  older  ewes.  Similar  pasturing  was  carried 
on.  in  1915,  partly  in  cooperation  with  the  land  owners  in  fencing 
small  laterals  so  that  herding  would  not  be  required.  The  in- 
crease in  the  herd  and  returns  from  the  wool  more  than  paid  the 
cost  of  grazing.  An  average  of  about  15  sheep  or  20  goats  were 
used  per  mile  of  canal  and  laterals.  In  other  sections  the  results 
with  grazing  sheep  have  not  always  been  successful.  Where  the 
growth  is  less  nourishing  than  Johnson  grass,  it  is  more  difficult 
to  maintain  the  sheep  in  good  condition  although  weed  growth 
can  be  restricted.  Occasionally  the  presence  of  poisonous  weeds 
make  grazing  impractical.  Ownership  of  the  sheep  by  the  canal 
company  is  preferable  if  close  grazing  is  desired.  Other  owners 
are  more  largely  interested  in  the  growth  of  the  sheep  than  in 
the  maintenance  of  the  canals. 

Mowing. — Mowing,  both  hand  and  machine,  is  often  used. 
Where  the  banks  are  fairly  even  and  the  space  is  sufficient  the 
cost  with  mowing  machines  is  much  less.  For  small  laterals 
hand  mowing  may  be  cheaper.  Some  hand  work  around  struc- 
tures may  be  needed  in  connection  with  machine  mowing. 
Various  makes  of  mowers  can  now  be  secured  with  which  the 
cutter  bar  can  be  operated  on  a  slope,  either  up  or  down. 
These  permit  running  the  mower  on  the  top  of  the  banks  and 
mowing  down  the  slopes  on  slopes  as  steep  as  1  to  1.  Mow- 
ing is  not  as  successful  with  Russian  thistle  due  to  the  close- 
ness to  the  ground  with  which  it  grows  and  to  its  collection 
in  front  of  the  machine.  Many  weeds  can  be  cut  prior  to 
seeding;  if  sweet  clover  is  cut  before  blooming,  new  growth  will 
start.  An  experienced  team  and  driver  can  accomplish  econom- 
ical results  on  banks  which  are  quite  rough  and  irregular.  In 
clearing  canals,  the  material  removed  should  be  uniformly  dis- 
tributed on  the  banks  if  these  are  to  be  machine  mowed.  Under 
normal  conditions  a  mowing  machine  should  do  the  work  of  8  to 
12  men  mowing  by  hand.  One  mowing  per  season  will  be  suffi- 
cient in  some  cases,  in  other  two  or  three  may  be  required.  The 
cost  of  mowing  is  usually  from  $1.00  to  $1.50  per  acre  per  cutting. 

Chemical  Control. — Various  chemical  solutions  for  the  purpose 
of  controlling  vegetation  have  been  used  with  field  crops,  on 


30  IRRIGATION  SYSTEMS 

railroad  rights  of  way  and  to  a  limited  extent  on  canal  banks. 
There  are  two  general  methods  of  treatment:  in  one  of  these, 
usually  known  as  the  root-absorption  method,  the  vegetation  is 
controlled  by  adding  sufficient  amounts  of  the  herbicide  to  render 
the  soil  sterile  so  that  any  plants  are  killed  or  seed  prevented  from 
growing  by  the  absorption  of  the  poisons  in  the  soil ;  in  the  other 
method,  usually  known  as  the  leaf -absorption  method,  the  poison 
is  applied  as  a  spray  to  the  portion  of  the  plant  above  ground, 
dependence  being  placed  on  the  absorption  of  the  chemical  by 
the  plant  in  sufficient  quantity  to  cause  its  death  or  its  failure 
to  mature  seeds.  The  root-absorption  method  may  be  applied  to 
canal  banks  as  sterility  may  be  desirable;  it  is  not  suited,  how- 
ever, to  agricultural  lands.  The  leaf-absorption  method  is  less 
expensive  although  the  results  obtained  may  be  only  temporary. 
Experiments  on  the  use  of  such  herbicides  have  been  made  by 
Mr.  G.  P.  Gray  of  the  California  Agricultural  Experiment  Sta- 
tion, from  whose  reports  the  following  information  is  mainly 
taken. 

Of  the  various  chemicals  used  arsenic  in  the  form  of  sodium 
arsenite  combines  effectiveness  with  relatively  low  cost.  Stock 
solutions  were  prepared  by  dissolving  arsenic  trioxide  in  sodium 
hydroxide  and  water  so  that  each  gallon  of  the  solution  contains 
4  pounds  of  arsenic  trioxide.  For  use  this  can  be  diluted  in  the 
proportion  of  1  to  100. 

For  the  leaf-absorption  method  the  proportion  of  about  300 
gallons  of  the  diluted  solution  or  12  pounds  of  arsenic  trioxide 
and  6  pounds  of  sodium  hydroxide  per  acre  are  recommended. 
The  cost  per  acre  of  the  materials  for  such  a  treatment  is  about 
$1.50.  It  was  found  that  such  a  solution  was  effective  in  killing 
the  plants  of  morning  glory  in  all  cases.  When  applied  in  the 
dormant  periods  of  growth,  it  was  found  that  the  roots  were  also 
killed  to  depths  of  2  to  4  feet.  These  results  were  secured  in  the 
relatively  humid  coast  areas  of  California;  in  the  more  arid  inte- 
rior the  results  were  less  satisfactory,  apparently  due  to  the  drying 
of  the  spray  before  its  absorption  by  the  plants.  The  emulsify- 
ing of  the  solution  with  soap  or  the  use  of  a  water  spray  in  ad- 
vance of  the  arsenic  solution  are  recommended  for  such  arid 
conditions.  No  injurious  effects  to  the  soil  were  noticed  from 
six  successive  applications  of  this  spray.  On  other  weeds,  the 
spray  was  most  effective  on  those  having  broad  leaves.  For 
grasses  the  addition  of  soap  increased  the  effect.  A  solution  of 


GENERAL  MAINTENANCE  31 

acid  sludge  and  water  as  well  as  acid  tar  appeared  to  be  especially 
effective  on  grasses. 

In  tests  of  the  root-absorption  method  the  arsenic  solutions 
also  gave  the  best  results.  Solutions  of  sodium  cyanide  were 
tried  with  less  satisfactory  results  both  as  to  effects  and  as  to 
costs  than  were  secured  with  arsenic.  Sulphuric  acid  solutions 
were  also  effective  but  high  in  cost.  Carbon  bisulphide,  applied 
at  the  rate  of  10  fluid  ounces  per  square  yard,  was  effective.  Iron 
sulphate  and  copper  sulphate  appeared  to  be  of  no  value  for  the 
control  of  the  morning  glory.  Acid  sludge  which  is  a  waste  prod- 
uct in  the  refining  of  petroleum  distillates  with  sulphuric  acid 
was  also  used.  The  cost  per  acre  of  materials  for  such  root- 
absorption  treatment  was  about  $120  where  sufficient  arsenic 
trioxide  was  used  to  control  morning  glory,  about  900  pounds 
per  acre  being  required,  and  about  $40  per  acre  where  300  pounds 
per  acre,  which  controlled  all  plants  except  morning  glory,  was 
used.  The  cost  per  acre  with  sodium  cyanide  and  carbon  bi- 
sulphide was  about  $300  and  with  sulphuric  acid  about  $250. 

Seeded  Grasses. — Many  efforts  have  been  made  to  find  some 
form  of  beneficial  or  even  unobjectionable  plant  which  could  be 
cheaply  established  on  canal  banks  and  which  could  maintain 
itself  there.  Some  success  has  been  attained  but  usually  at  a 
relatively  high  cost.  The  upper  parts  of  canal  banks  are  often 
very  dry  and  composed  of  relatively  infertile  soil  taken  from  the 
deeper  portion  of  the  excavation.  It  is  difficult  to  secure  a  stand 
of  seeded  grasses  which  can  maintain  itself  against  the  native 
weeds  under  such  conditions. 

Experiments  with  different  grasses  have  been  made  on  the 
Belle  Fourche  project  in  South  Dakota.  The  following  mixture 
per  acre  seeded  was  recommended  for  use  there  as  the  results 
of  these  tests:  brome  grass  (Bromus  inermis),  6  pounds;  western 
wheat  grass,  6  pounds;  alfalfa,  6  pounds;  redtop,  2  pounds. 
Seeding  should  be  done  in  the  spring  when  the  ground  is  moist 
and  no  grazing  should  be  permitted  during  the  first  two  seasons  in 
order  to  secure  a  good  sod.  Western  wheat  grass  is  a  native  of 
South  Dakota  and  is  the  most  drought-resistant  of  the  grasses 
there.  It  is  slow  to  start,  however,  making  it  difficult  to  secure 
a  stand.  Brome  grass  and  alfalfa  gave  good  results  in  most 
cases.  When  a  stand  is  once  secured,  alfalfa  being  deep-rooted 
may  be. able  to  maintain  itself  under  moisture  conditions  which 
shallow  rooted  grasses  could  not  survive.  In  many  localities 


32  IRRIGATION  SYSTEMS 

the  use  of  alfalfa  on  canal  banks  is  not  desirable  as  its  roots  attract 
burrowing  animals  which  may  injure  the  banks. 

On  the  Boise  project  clover  and  blue  grass  have  been  tried. 
The  cost  was  $14.85  per  acre  and  stands  were  secured  only  where 
the  banks  could  be  irrigated,  such  as  below  drops.  Fall-sown 
rye  at  a  cost  of  $2.60  per  acre  gave  the  best  results.  Rye  is  self- 
seeding  and  after  a  few  years  tends  to  exhaust  the  fertility  of  the 
soil  so  that  little  else  will  grow.  It  is  also  extensively  used  to 
control  blowing  soils.  On  the  Truckee  Carson  project,  native 
.blue  joint  or  blue  stem  grass  has  proven  itself  to  be  hardy.  It 
spreads  both  by  runners  and  by  seeding.  A  stand  is  more  easily 
secured  by  setting  roots  than  by  seed.  Gophers  do  not  eat  its 
roots  to  any  extent.  On  some  California  systems,  white  clover 
has  given  good  results.  This  does  not  grow  to  sufficient  height 
to  interfere  with  the  use  of  the  banks  and  will  spread  from  the 
moister  soil  to  the  dryer  tops  of  the  banks.  In  Montana  a  mix- 
ture of  Kentucky  blue  grass  and  timothy  in  proportion  of  2  to  1 
has  been  recommended  for  small  canals.  On  large  canals  native 
blue  stem  can  be  used;  on  the  smaller  ditches  its  growth  may  be 
too  rank. 

Miscellaneous  Methods. — Where  the  soil  does  not  blow,  clean 
cultivation  can  be  used.  Such  harrowing  must  be  repeated  each 
year  and  is  a  relatively  expensive  method.  On  the  Boise  project 
harrowing  gave  fairly  satisfactory  results,  the  cost  being  $4.85 
per  acre  handled  per  year.  Several  treatments  per  year  may  be 
required.  Oiling  canal  banks  to  prevent  weed  growth  has  been 
tried  in  a  few  cases.  The  results  have  not  generally  been  success- 
ful. If  such  treatments  are  sufficiently  thorough  to  give  per- 
manent results  in  weed  prevention  the  cost  is  higher  than  is 
warranted.  Less  thorough  methods  have  little  effect. 

PROTECTION    OF    CANALS    IN    BLOWING    SOILS 

Canals  in  light  soils  often  give  trouble  due  to  the  blowing  of 
the  banks  or  wind  erosion.  Such  troubles  are  due  both  to  the 
filling  of  the  canal  cross-section  by  such  drifting  soil  and  to  the 
eroding  of  the  banks  so  as  to  reduce  their  strength.  Rye  has 
been  used  in  a  number  of  cases  and  has  been  found  to  be  able  to 
grow  under  conditions  where  other  plants  cannot  maintain  them- 
selves. Various  other  methods  of  protection  have  also  been 
used. 


GENERAL  MAINTENANCE  33 

On  the  North  Platte  project  there  are  about  50  miles  of  main 
canal  in  soils  which  blow.  In  some  cases  an  unprotected  bank 
with  a  12-foot  crown  has  been  lowered  3  feet  in  6  months.  A 
number  of  methods  of  protection  have  been  tried,  the  following 
summary  of  their  experience  being  taken  from  the  Reclamation 
Record  for  September,  1913.  The  canal  has  been  fenced  against 
range  stock  as  it  was  found  that  cattle  loosened  the  soil  and  caused 
it  to  blow  more  easily.  Fencing  was  also  necessary  to  protect 
the  coverings  used.  The  fencing  has  also  enabled  sand  grass  to 
establish  itself  and  to  hold  the  soil.  In  October,  1909,  12,000 
linear  feet  of  new  bank  were  covered  with  a  light  coat  of  stable 
manure  at  a  cost  of  1J£  cents  per  linear  foot.  By  March,  1910, 
this  had  nearly  all  disappeared.  As  soon  as  holes  are  opened  in 
such  covering,  the  wind  undermines  the  straw  and  gradually 
carries  it  away.  Straw  will  not  give  protection  unless  spaded  or 
disked  into  the  ground.  About  45,000  linear  feet  were  covered 
on  the  top  and  outside  slope  with  a  3-  or  4-inch  layer  of  gravel 
at  a  cost  of  21  cents  per  linear  foot  or  81  cents  per  cubic  yard. 
This  has  been  found  to  be  the  most  permanent  protection  and  is 
used  where  the  gravel  haul  is  not  over  1J£  miles.  About  % 
mile  of  the  outer  slope  of  the  canal  banks  has  been  covered  with 
brush  at  a  cost  of  20  cents  per  linear  foot.  This  has  been  quite 
satisfactory  but  is  liable  to  destruction  by  fire. 

About  5  miles  of  canal  were  covered  with  Russian  thistle  held 
in  place  by  woven  wire  at  a  cost  of  1 1  cents  per  square  yard,  of 
which  4  cents  was  for  wire  and  7  cents  for  labor.  This  is  recom- 
mended for  narrow,  steep  or  ragged  banks.  The  sand  which  is 
caught  in  such  lining  strengthens  the  bank.  On  flat  slopes,  the 
weeds  were  plowed  in,  the  cost  on  60,000  square  yards  being 
6.1  cents  per  square  yard.  These  weeds  accumulate  in  the  canal 
during  the  winter  and  can  be  economically  used  in  such  pro- 
tection. Cement  coating,  calcium  chloride,  crude  oil,  sugar 
syrup  and  coal  tar  were  also  tried  but  none  of  these  methods 
proved  satisfactory. 

Relatively  high  velocities  are  desirable  in  the  portions  of 
canals  passing  through  blowing  soils  as  the  finer  sand  blown  into 
the  canal  may  be  partially  eroded  by  the  water  and  the  reduction 
in  area  distributed  over  a  longer  length  of  canal.  Wind  breaks 
located  far  enough  from  the  canal  to  prevent  the  sand  collect- 
ing in  the  canal  may  be  used.  Sand  fences  similar  to  those 
used  on  railroads  may  be  used  until  more  permanent  relief  can 

3 


34 


IRRIGATION  SYSTEMS 


be  secured.  Using  wide  rights  of  way,  such  as  1,000  feet,  and 
leaving  the  native  vegetation  on  the  unused  portion  of  the  right 
of  way  or  the  planting  of  rye  or  other  growth,  may  be  sufficient. 

CANAL  SCREENS 

The  practice  in  regard  to  the  use  of  weed  screens  varies  quite 
widely.  On  some  systems,  such  screens  may  be  provided  at  the 
inlets  of  all  siphons  and  at  other  feasible  locations.  On  other 
systems,  no  screens  may  be  used.  The  tendency  is  apparently 
away  from  the  use  of  such  screens,  many  taking  the  risk  of 
stoppage  of  siphons  and  gates  in  preference  to  the  risk  of  stop- 


PLAN 


ELEVATION 

FIG.  2. — Coarse  weed  screen  used  in  wood  flumes  by  the  Bitter  Root  Valley 

Irrigation  Co. 

page  of  screens.  Ordinarily  weeds  and  drift  carried  in  the  canal 
will  be  carried  through  the  siphons  due  to  the  greater  velocity 
in  the  siphon,  although  this  may  not  be  the  case  at  the  ends  of 
the  seasons  when  the  discharge  is  smaller.  Where  the  siphons 
are  small,  the  danger  of  clogging  is  greater  and  screens  may  be 
used  on  laterals  on  systems  where  no  screening  is  practiced  on 
the  main  canal.  Weeds  frequently  collect  on  turnouts  or  checks 
and  affect  the  flow  of  the  water,  in  some  cases  to  a  sufficient 
extent  to  cause  injury  to  the  canal.  Similar  injuries,  however, 
are  liable  to  be  caused  by  the  collection  of  such  weeds  on  weed 
screens  unless  they  are  frequently  cleaned.  The  danger  of  such 


• 


GENERAL  MAINTENANCE 


35 


injury  has  caused  night  patrolling  to  be  practiced  in  a  few  cases; 
ordinarily  patrolling  for  such  cases  will  not  be  required  after 
the  first  few  years  of  operation,  as  settlement  or  other  means 
of  prevention  of  weed  growth  should  remove  the  source.  Such 
weeds  reach  the  canal  from  adjoining  lands  below  the  headgate 


10'  0^ 


PLAN  OF  SCREEN         To 

Slope  of 
Bank 

Top  of  Lining 


SECTION    BB 


2x2  Seat 
tor  ScreenX 

*  -«?  s^^io'o"     >[^foH  f 

y 

•*H 

Slope  Floor  to  Fit 
^       t                          Bottom  of  Pipe  y 

20  Pipe 

t       £_    SECTION 

\<                   n'o" 

> 

1                           A 

2  Concrete  Lining 

Vi 

-4- 

1% 

53 

F           Direction  of  Flow  —  »- 

1                   £ 

f 

\ 

"     Slope  may  vary  from 
1:1  to  IH-I 

~~~Jjjl 

A 

PLAN  WITH  SCREEN   REMOVED 


SECTION  AA 

FIG.  3. — Weed  screen  used  at  inlet  of  20-inch  pipe  lines  on  Umatilla  project. 

so  that  the  fish  or  other  screens  used  at  the  diversion  will  not 
prevent  trouble  on  the  canals. 

A  type  of  weed  screen  used  on  the  Bitter  Root  Valley  Irriga- 
tion Co.'s  system  in  Montana  is  shown  in  Fig.  2.  This  is 
placed  in  wood  flumes.  The  main  canal  is  of  considerable  length 
and  contains  a  number  of  flumes  and  siphons.  When  the  screens 

UNIVERSITY  OF  CALIFORNIA 
DEPARTMENT  OF  CIVIL  ENGINEERING 


36  IRRIGATION  SYSTEMS 

are  free  from  trash,  the  water  flows  smoothly  through  the  racks. 
In  case  weeds  are  caught  on  the  rack  so  as  to  clog  the  screen,  the 
water  has  an  opportunity  to  pass  between  the  two  sections  of 
the  screen  as  indicated  by  the  arrow.  This  will  cause  cross- 
currents which  makes  this  screen  unsuited  to  earth  canals;  in 
flumes  or  lined  sections  such  currents  cannot  cause  erosion. 
Ordinary  rack  screens  with  racks  of  J^  X  IJ^-inch  strap  iron  % 
inch  apart  are  used  at  the  inlets  of  siphons.  These  are  placed 
on  a  slope  of  1  on  2  with  the  top  somewhat  below  the  top  of  the 
bank  or  flume.  In  case  of  clogging,  the  flow  may  pass  over  the 
top  of  the  screen  before  backing  over  the  bank. 

In  Fig.  3  is  shown  a  type  of  weed  screen  developed  on  the 
Umatilla  project  for  use  in  lined  laterals  above  pipe  siphons. 
Where  such  screens  have  been  cleaned  daily  they  have  been 
satisfactory,  breaks  not  only  being  avoided  but  a  more  regular 
service  being  maintained.  These  have  been  used  in  laterals 
up  to  20  second-feet  capacity.  Some  debris  is  left  on  the  screen 
to  give  sufficient  velocity  in  the  depressed  section  to  prevent 
sand  deposits.  These  screens  have  been  installed  in  old  sections 
at  a  cost  of  about  $25;  if  placed  at  the  time  of  construction  of 
the  lateral,  the  cost  should  not  exceed  $20.  The  advantages  of 
this  form  of  screen  are  the  large  area  and  the  large  quantity  of 
drift  which  can  be  retained  before  serious  checking  of  the  flow 
takes  place. 

BURROWING  ANIMALS 

In  practically  all  irrigated  sections  some  of  the  various  forms 
of  burrowing  animals  give  trouble  in  canal  maintenance.  Their 
holes  are  points  of  weakness  at  which  canal  breaks  may  start. 
Such  breaks  are  particularly  liable  to  occur  when  the  water 
surface  in  the  canal  is  raised  so  as  to  be  above  new  holes.  Such 
holes  are  also  more  troublesome  and  dangerous  in  fills.  In  some 
localities  the  prevention  or  repair  of  breaks  caused  by  such 
animals  may  be  the  largest  single  item  in  the  cost  of  canal 
maintenance,  particularly  on  the  laterals.  Where  water  is 
rotated  between  laterals  the  burrows  may  be  built  in  the  banks 
during  the  time  water  is  out.  When  water  is  turned  in  again 
the  holes  may  start  breaks.  In  some  cases  canals  are  operated 
under  checks  so  as  to  maintain  a  uniform  depth  of  water  in  the 
canal  throughout  the  season.  The  burrows  in  such  cases  will 
be  above  the  line  of  saturation  in  the  banks. 


GENERAL  MAINTENANCE  37 

The  kind  of  animals  causing  the  damage  varies  in  different 
localities.  Also,  the  local  names  for  the  same  animal  are  liable 
to  differ,  causing  much  confusion  in  discussing  means  for  their 
control.  The  most  successful  methods  of  control  are  based  on 
a  knowledge  of  the  habits  of  the  different  animals,  and  uni- 
formity in  names  is  essential  if  such  methods  are  to  be  under- 
stood. Much  work  has  been  done  in  studying  these  animals  in 
relation  to  the  injury  which  they  cause  to  field  crops,  the  results 
of  which  have  been  published  in  various  bulletins,  references  to 
which  are  given  at  the  end  of  the  chapter.  The  data  regarding 
poisons  and  the  habits  of  the  animals  are  taken  mainly  from  these 
references. 

The  most  generally  employed  methods  of  control  are  poison- 
ing and  trapping.  A  number  of  special  methods  have  also 
been  used  for  particular  conditions. 

Pocket  Gophers. — The  animal  of  most  general  occurrence  and 
one  giving  much  trouble  is  the  pocket  gopher.  The  gopher  is 
also  blamed  for  much  damage  caused  by  ground  squirrels,  the 
term  gopher  being  used  in  many  localities  to  cover  all  small 
burrowing  animals.  The  habits  and  methods  of  handling 
gophers  and  ground  squirrels  differ  materially  and  the  two  types 
should  not  be  confused. 

Pocket  gophers  differ  in  size  from  that  of  a  small  mole  to  that  of 
a  large  rat,  a  large  number  of  varieties  being  recognized.  All  are 
short-legged,  have  small  ears  and  eyes  and  short  smooth  hair. 
The  most  distinctive  characteristics  are  the  large  pockets  from 
which  their  name  is  derived.  These  are  on  the  outside  of  the 
head  and  may  be  from  1J^  to  2  inches  deep,  extending  back  under 
the  skin  of  the  shoulder.  The  pockets  are  used  for  carrying  the 
food  secured  in  burrowing.  When  filled,  the  pockets  more  than 
double  the  size  of  the  head.  Apparently  pocket  gophers  do  not 
hibernate. 

Pocket  gophers  are  found  over  practically  the  entire  western 
half  of  the  United  States,  extending  into  Canada  and  Mexico. 
They  are  especially  abundant  in  fertile  soils  where  their  burrows 
cause  much  inconvenience  and  loss  to  crops.  Their  food  is 
entirely  vegetative  such  as  roots,  bulbs  and  cultivated  crops. 
These  are  cut  into  sections,  when  encountered  in  their  burrowing, 
and  put  into  the  pocket  to  be  carried  to  the  nest.  Apparently 
they  do  not  require  water  except  such  as  is  secured  in  their  food, 
as  many  desert  species  thrive  for  long  periods,  such  as  a  year  or 


38  IRRIGATION  SYSTEMS 

more,  where  water  is  not  available.  Their  burrowing  into  ditch 
banks  is  for  the  purpose  of  escaping  the  flooding  that  may  be 
given  their  burrows  in  adjacent  irrigated  fields  rather  than  to 
search  for  food  or  water. 

The  burrows  or  tunnels  are  located  from  6  inches  to  a  foot 
below  the  surface,  are  1J^  to  3  inches  in  diameter  and  have  a 
length  varying  from  a  winding  network  of  passages  to  long  direct 
lines.  The  lines  of  burrows  in  fields  are  marked  by  mounds  of 
earth  spaced  generally  about  15  feet  apart.  After  pushing  out 
the  loose  earth  in  the  mounds,  the  openings  are  closed  from 
within,  leaving  no  open  runways.  In  this  they  are  distinctly  dif- 
ferent from  ground  squirrels.  Pocket  gophers  are  rarely  seen 
as  they  do  not  emerge  from  their  burrows. 

Among  the  natural  enemies  of  the  gophers  are  the  hawks  and 
owls  and  coyotes  who  may  pick  them  up  at  the  outlets  of  the 
burrows.  Badgers  occasionally  dig  them  out.  Weasels,  who 
follow  them  into  their  burrows,  are  probably  their  greatest 
enemies  as  there  is  practically  no  escape  for  the  gopher.  Gopher 
snakes  are  so  called  from  their  habit  of  catching  gophers. 

Pocket  gophers  can  be  poisoned  successfully  if  the  poison  is 
placed  in  their  burrows.  This  can  be  done  by  following  down 
the  closed  outlet  in  the  mounds  until  the  burrow  is  reached  and 
placing  the  bait  in  the  burrow.  Better  results  are  usually  secured 
with  some  vegetable  such  as  potatoes,  parsnip  or  carrots  cut  into 
pieces  about  %  inch  square  and  1  inch  long.  Strychnine  can 
be  sifted  over  the  bait  using  %  ounce  of  powdered  strychnine 
(alkaloid)  and  one-tenth  as  much  saccharine  to  4  quarts  of 
dampened  bait  or  a  small  crystal  of  strychnine  can  be  inserted  in 
a  slit  in  each  bait. 

Traps  may  also  be  set  in  the  burrows.  A  number  of  different 
types  are  on  the  market  which  will  give  good  results.  Some  of 
these  are  arranged  to  be  sprung  by  the  earth  which  the  gopher 
pushes  ahead  of  him  in  the  burrow,  catching  the  gopher  behind 
the  earth.  Traps  are  more  difficult  to  set  for  gophers  as  the 
burrow  must  be  opened. 

Ground  Squirrels. — Ground  squirrels  are  of  common  occurrence 
throughout  the  West.  There  are  several  varieties  of  these.  The 
short-tailed  gray  Piute  squirrel  is  found  in  the  Great  Basin  and 
adjacent  areas.  The  flickertail  or  Richardson  ground  squirrel 
is  found  in  Montana  and  adjoining  States.  The  larger  and 
darker  Columbian  ground  squirrel  is  common  in  the  Columbia 


GENERAL  MAINTENANCE  39 

River  drainage  area.  If  disturbed,  this  squirrel  may  stand  erect 
for  an  instant  taking  a  position  which  has  caused  them  to  be 
called  the  "picket  pin."  In  California  the  gray  squirrel  known 
as  the  California  Digger  or  Beechy  ground  squirrel  is  distributed 
widely.  These  do  not  hibernate  in  the  warmer  portions  of  the 
State.  Chipmunks  usually  inhabit  timbered  areas  and  seldom 
cause  trouble  to  canals.  One  variety  known  as  the  sage-brush 
chipmunk  may  be  found  along  ditches.  These  are  not  extensive 
burrowers  although  they  may  use  the  burrows  of  other  animals. 
Chipmunks  do  not  hibernate.  They  usually  eat  poisoned  grain 
readily. 

In  all  except  the  hotter  climates  ground  squirrels  hibernate  for 
several  months  of  the  year.  Seeds  and  green  vegetation  form 
their  principal  food.  Their  burrows  are  generally  not  extensive 
although  they  may  be  larger  in  the  later  summer  season  than  in 
the  spring.  Ground  squirrels  are  diurnal  in  habit  and  are  easily 
seen.  They  prefer  to  build  their  burrows  on  small  elevations 
so  that  they  may  have  a  wide  view  from  their  runways  as  a  pro- 
tection against  natural  enemies.  This  is  probably  the  reason 
they  are  so  frequently  found  along  ditch  banks. 

As  their  burrows  are  usually  single  they  may  be  readily  killed 
with  carbon  bisulphide.  Trapping  will  also  generally  give  good 
results,  particularly  in  the  earlier  season  when  mating  is  taking 
place  and  the  squirrels  are  less  careful. 

Poisoning  is  very  generally  practiced,  the  bait  being  placed  at 
or  near  the  mouth  of  the  burrow.  The  readiness  with  which  the 
poison  will  be  eaten  depends  on  the  availability  of  other  food. 
It  is  most  successful  early  in  the  season  when  the  squirrels 
emerge  from  hibernation  or  before  green  food  becomes  abundant. 
Grain  may  be  used  in  the  early  season,  later  more  succulent  bait 
such  as  alfalfa,  turnips  or  beets  may  be  eaten. 

Muskrats. — Muskrats  differ  from  the  other  animals  in  that 
they  burrow  into  the  banks  from  the  inside  of  the  canal  below  the 
water  surface  rather  than  from  the  outside.  They  may  enter  the 
bank  a  foot  or  two  below  the  water  surface  and  burrow  through 
to  the  outside.  Screens  can  be  placed  across  the  ditches  arranged 
to  trap  them  and  prevent  their  entrance  to  canals.  Usually 
the  difficulty  caused  in  keeping  such  screens  free  from  drift  will 
make  the  method  impractical.  Muskrats  have  a  value  for  their 
fur  and  may  be  trapped  for  this  purpose  alone.  They  are  also 
eaten.  Muskrats  may  be  poisoned  with  strychnine  or  arsenic 


40  IRRIGATION  SYSTEMS 

in  carrots,  parsnip  or  turnips.  If  such  poisons  are  placed  along 
the  ditch  care  should  be  used  to  prevent  the  bait  getting  into  the 
ditch  and  being  carried  to  farm  animals.  Trapping  or  shooting 
will  usually  give  the  best  results.  On  some  systems  bounties 
of  20  or  25  cents  are  paid  for  muskrats  caught  on  the  canals,  on 
others  a  guaranteed  price  for  the  skins  may  be  maintained  as  an 
inducement  to  trappers. 

Other  Animals. — Prairie  dogs  do  not  cause  much  trouble  in 
canal  maintenance.  Their  distribution  is  limited  to  the  Rocky 
Mountains  and  Great  Plains  areas  to  the  east.  Their  habit  of 
living  in  towns  makes  them  destructive  of  crops.  They  seldom 
infest  canal  banks. 

Some  of  the  various  forms  of  meadow  mice  or  rats  may  cause 
trouble  in  the  smaller  laterals,  particularly  around  structures. 
The  larger  kangaroo  rats,  so  called  -because  of  their  long  hind 
legs  used  in  travelling  by  leaps  or  hops  similarly  to  a  kangaroo, 
may  sometimes  make  burrows  in  ditch  banks  as  they  prefer 
slight  elevations  or  embankments.  Rats  are  most  easily  con- 
trolled through  protection  to  their  natural  enemies  such  as 
hawks,  owls,  herons  and  badgers,  skunks,  snakes  and  weasels. 
Poisoning  as  for  ground  squirrels  can  also  be  used. 

Badgers  live  on  the  various  forms  of  burrowing  animals  which 
cause  injury  to  ditch  banks.  When  in  pursuit  of  such  animals, 
a  badger  may  dig  into  and  injure  the  bank  but  the  benefit  by 
continuous  destruction  of  the  other  animals  may  be  greater  than 
such  occasional  loss.  On  some  systems  they  are  destroyed. 
Trapping  or  shooting  are  usual  methods.  Weasels  are  also  of 
benefit  as  they  kill  gophers  and  mice.  They  are  very  active 
and  may  exterminate  gophers  in  narrow  areas.  Skunks  are  more 
beneficial  than  harmful.  Occasionally  when  digging  for  mice 
and  small  rodents  they  may  cause  damage  to  ditch  banks  but 
the  benefit  derived  from  the  destruction  of  such  rodents  is  of 
much  value. 

METHODS  OF  CONTROL  OF  BURROWING  ANIMALS 

Poisoning. — Strychnine  forms  the  basis  of  most  of  the  poisons 
used.  It  has  the  advantage  that  its  action  is  certain  and  its 
character  is  generally  well  known.  Its  taste  is  so  bitter  that  it 
is  not  liable  to  be  eaten  by  children  through  mistake.  Strychnia 
sulphate  is  soluble  both  in  hot  water  and  in  fruit  juices.  The 


GENERAL  MAINTENANCE  41 

poison  may  be  used  with  a  wide  variety  of  bait  depending  upon 
the  feeding  habits  of  the  animal  being  sought. 

Grain,  such  as  wheat,  barley,  oats  or  corn,  either  whole  or 
crushed,  is  most  generally  used.  It  may  be  prepared  by  glazing 
the  surface  with  a  solution  of  the  poison  or  by  the  absorption 
of  the  solution  into  the  grain.  Glazing  is  quicker  in  action.  It 
has  also  been  found  that  ground  squirrels  will  be  killed  by  the 
absorption  of  strychnine  from  glazed  grain  carried  in  their  cheek 
pouches  before  it  is  actually  eaten.  If  used  at  a  season  when 
rain  may  be  expected,  the  poison  may  be  washed  from  the  glazed 
grain  before  it  is  eaten.  Such  poisoned  grain  can  usually  be 
prepared  for  4  or  5  cents  per  pound. 

For  preparing  poisoned  oats  the  following  method  is  recom- 
mended in  Circular  4  of  the  North  Dakota  Experiment  Station: 
Mix  thoroughly  1  ounce  strychnine  alkaloid  (powdered)  and  1 
ounce  baking  soda.  Sift  this  into  %  pint  of  thin  hot  starch 
paste,  stir  to  a  creamy  mass.  The  starch  paste  is  made  by  dis- 
solving 1  heaping  tablespoonful  of  dry  gloss  starch  in  a  little 
cold  water  which  is  then  added  to  %  pint  of  boiling  water.  Boil 
and  stir  constantly  until  a  clear  thin  paste  is  formed.  Add  Y± 
pint  heavy  corn  syrup  and  a  tablespoon  of  glycerine  and  stir 
thoroughly.  Pour  this  poison  solution  over  20  quarts  of  clean 
oats  and  mix  thoroughly  so  that  each  grain  is  coated.  Prepare 
24  to  48  hours  before  using. 

Crushed  grain  or  cornmeal  may  be  used.  On  the  Orland 
project  a  mixture  of  oatmeal,  cornmeal,  salt,  sugar  and  strych- 
nine has  given  good  results.  A  poison  recommended  after  many 
trials  by  S.  E.  Piper  of  the  U.  S.  Department  of  Agriculture  is 
as  follows:  Dissolve  1  ounce  of  strychnia  sulphate  and  2  ounces 
of  borax  in  2  quarts  of  hot  water  in  a  closed  vessel,  stirring  occa- 
sionally for  20  minutes  or  until  completely  dissolved.  Then 
add  6  quarts  of  warm  water,  and  sprinkle  this  poisoned  solution 
over  30  pounds  of  rolled  or  crushed  wheat,  stirring  and  mixing 
thoroughly  until  it  is  all  absorbed.  Place  %  teaspoonful  of  the 
poisoned  grain  near  the  entrance  of  each  occupied  burrow  or  in 
each  runway. 

Alfalfa  or  green  grain  heads  may  be  used  if  the  animals  do 
not  take  the  grain  readily.  One  ounce  of  strychnine  sulphate 
may  be  dissolved  in  2  gallons  of  boiling  water  and  sprinkled  over 
16  pounds  of  leafy  alfalfa  chopped  into  2-inch  lengths.  Green 
grain  heads  in  the  milk  or  soft  dough  stages  may  be  soaked  for 


42  IRRIGATION  SYSTEMS 

15  to  24  hours  in  a  solution  twice  as  strong  as  the  above.  These 
green  poisons  should  be  distributed  near  the  holes  early  in  the 
morning.  They  are  temporary  as  the  animals  will  not  eat  them 
when  wilted.  Six  to  eight  grain  heads  should  be  used  per 
squirrel  hole. 

Trapping. — Either  the  ordinary  No.  0  steel  traps  or  some  of 
the  so-called  guillotine  traps  may  be  used.  There  are  a  number 
of  special  traps  for  pocket  gophers  on  the  market  which  give 
good  results.  It  is  necessary  to  insert  the  traps  for  gophers  in 
the  underground  runways,  those  for  squirrels  are  placed  at  the 
entrance  of  the  burrows.  Trapping  may  be  done  by  the  ditch 
riders  incidentally  with  their  other  duties,  or  bounties  may  be 
paid  for  those  caught.  The  latter  method  is  sometimes  used 
in  connection  with'  campaigns  against  squirrels  and  gophers  in 
farm  fields.  Ten  cents  per  head  is  usually  paid,  the  trapping 
generally  being  done  by  the  local  boys.  The  cost  with  regularly 
hired  labor  will  usually  be  higher  than  this.  On  the  North  Platte 
project  the  land  owners  assessed  themselves  3  cents  per  acre 
to  pay  bounties  in  1916.  In  1915  bounties  were  paid  on  over 
33,000  scalps. 

Suffocation. — For  animals  having  short  or  deep  burrows  suffo- 
cation with  the  fumes  of  carbon  bisulphide  will  often  give  good 
results.  This  is  most  effective  in  moist  soils,  as  after  a  rain, 
as  the  gas  is  dissipated  to  a  less  extent  in  the  surrounding  soil. 
From  1  to  2  tablespoons  of  the  bisulphide  should  be  placed  on 
some  absorbent  such  as  cotton  waste  or  manure  and  then  thrown 
as  far  down  the  burrow  as  possible.  The  opening  in  the  burrow 
should  be  closed.  A  heavy  gas  is  formed  which  sinks  to  the 
lower  levels  of  the  burrow  and  suffocates  the  animals.  Carbon 
bisulphide  can  usually  be  purchased  for  about  8  cents  per  pound 
in  50-pound  quantities.  From  %  to  1  ounce  per  burrow  is  used. 
It  should  be  handled  carefully  as  it  is  mildly  explosive  and 
inflammable. 

Suffocation  with  the  exhaust  fumes  of  an  automobile  is  reported 
to  have  been  effective  on  the  Klamath  project.  A  hose  was 
attached  to  the  exhaust  pipe  and  led  into  each  burrow.  The 
burning  of  powder  without  direct  explosion  has  also  been  tried. 
Actual  drowning  by  pouring  water  in  the  burrow  may  be  practiced 
with  some  forms  of  ground  squirrels. 

Natural  Control. — Certain  of  the  burrowing  animals  giving 
trouble  in  canal  banks  form  a  part  of  the  food  of  other  animals. 


GENERAL  MAINTENANCE  43 

Gophers  and  squirrels  are  the  prey  of  the  badger,  weasel,  skunk 
and  certain  varieties  of  hawks  and  owls.  The  destruction  of 
these  animals,  a  usual  result  of  settlement,  may  lead  to  a  marked 
increase  in  the  animals  comprising  their  food.  Unless  it  is 
certain  that  the  larger  animals  cause  more  harm  in  other  ways 
they  should  be  protected  for  their  control  of  the  burrowing 
pests.  This  is  particularly  true  of  the  birds.  With  badgers 
the  harm  done  may  exceed  the  benefit. 

Special  Methods. — For  badly  infested  portions  of  the  canal 
relatively  expensive  methods  of  prevention  may  be  warranted. 
Concrete  canal  lining  will  prevent  breaks  due  to  burrowing 
animals,  although  the  expense  is  not  warranted  for  such  pre- 
vention alone  except  in  extreme  cases.  On  the  Salt  River 
project  the  pasturing  of  sheep  has  been  found  to  prevent  injury 
by  burrowing  animals,  the  sheep  driving  them  out  of  closely 
pastured  banks,  'in  one  particularly  troublesome  length  of 
canal  on  this  project  a  trench  3  to  4  feet  deep  was  excavated 
2  to  4  feet  back  from  the  high-water  line.  In  this,  %-mch  mesh 
galvanized  wire  was  placed  and  the  trench  refilled.  The  mesh 
prevents  burrowing  through  the  entire  bank  from  either  direction. 
The  cost  was  from  20  to  30  cents  per  lineal  foot. 

The  use  of  a  wall  of  oil-filled  soil  in  the  canal  bank  has  also 
been  tried.  Holes  were  put  along  the  bank  and  filled  with  oil, 
the  walls  between  the  holes  being  broken  down  so  as  to  form  a 
wall  of  oiled  earth.  Gophers  do  not  dig  through  such  soils. 

In  fills  made  of  loose  dry  sand  the  sand  may  run  sufficiently  so 
that  the  animals  have  difficulty  in  keeping  their  burrows  open, 
thus  driving  them  to  other  locations.  It  may  be  practical  to  use 
the  sand  deposited  in  the  canal  and  removed  in  cleaning  for  the 
blanketing  of  fills  for  this  purpose. 

FENCING  CANAL  RIGHTS  OF  WAY 

The  questions  as  to  whether  canals  should  be  fenced  or  not  and 
if  fenced  who  builds  and  maintains  them  have  caused  much 
controversy  between  land  owners  and  canal  companies.  This  is 
particularly  true  of  the  question  of  permitting  fences  with  gates 
to  be  built  across  the  canals  at  road  lines  in  order  to  avoid  fencing 
the  canal  through  the  lands. 

The  legal  principles  regarding  fences  depend  largely  on  the 
nature  of  the  right  of  way.  Rights  of  way  are  of  two  general 


44  IRRIGATION  SYSTEMS 

classes:  (1)  where  the  canal  company  owns  the  right  of  way  in 
fee  simple,  that  is,  where  the  ownership  is  complete  and  similar 
to  the  farmer's  ownership  of  his  land;  and  (2)  where  only  a  right 
to  use  the  right  of  way  for  canal  purposes  or  what  is  termed  an 
easement  is  owned.  The  same  rules  apply  between  right  of  way 
owned  in  fee  simple  and  adjacent  farms  that  apply  between  two 
farms.  The  owner  of  adjacent  land  must  take  reasonable  pre- 
cautions to  prevent  damage  to  the  right  of  way  by  his  stock; 
failure  to  take  such  precautions  renders  the  land  owner  respon- 
sible for  resulting  damage.  The  canal  owner  is  under  no  obliga- 
tion to  place  fences  across  the  right  of  way  at  roads  and  cannot 
be  held  responsible  for  stock  which  may  either  go  from  or  onto 
adjoining  lands.  The  land  owner  must  secure  permission  from 
the  canal  owner  to  put  fences  across  such  rights  of  way  and  the 
canal  owner  may  require  such  conditions  as  the  construction  of 
suitable  gates  or  an  agreement  to  remove  on  notice  as  a  considera- 
tion for  such  permission. 

For  the  rights  of  way  held  as  easements  the  canal  owner  is 
known  as  the  dominant  estate  and  the  original  grantor  of  the 
easement  as  the  servient  estate.  In  such  cases  the  land  owner 
can  use  the  right  of  way  in  any  manner  which  will  not  interfere 
with  the  use  of  the  easement  for  canal  purposes  and  it  is  the 
canal  owner's  duty  to  fence  or  otherwise  protect  the  ditch  in  case 
he  wishes  to  protect  it  against  damage  from  the  ordinary  use  of 
the  land  by  the  land  owner.  In  Durfee  vs.  Garvey  (78  Cal.  546) 
it  was  held  that  the  canal  owner  cannot  recover  damages  for  the 
cost  of  canal  cleaning  made  necessary  by  the  trampling  of  the 
land  owner's  cattle. 

The  general  principles  have  been  summarized  as  follows  by 
Mr.  S.  C.  Wiel  in  his  work  on  "  Water  Rights  in  the  Western 
States." 

"It  is  the  ditch  owner's  duty  to  fence  or  otherwise  keep  the  ditch 
in  repair  against  damage  from  the  ordinary  use  of  the  land  by  the  land 
owner.  And  per  contra  if  the  cattle  drown  in  the  ditch,  the  ditch 
owner  is  not  liable  to  the  land  owner.  The  owner  of  the  servient  estate 
may  erect  fences  along  the  sides  of  a  ditch  or  artificial  water  course. 
Unless  it  is  expressly  stipulated  that  the  way  shall  be  an  open  one  or 
it  appears  from  the  terms  of  the  grant  or  the  circumstances  of  the  case 
that  such  was  the  intention  of  the  parties,  the  owner  of  the  servient 
estate  may  also  erect  gates  across  the  way,  provided  they  are  so  located 
and  constructed  as  not  unreasonably  to  interfere  with  the  use  of  the 
ditch." 


GENERAL  MAINTENANCE  45 

In  Utah  Idaho  Sugar  Co.  vs.  Stevenson  (97  Pac.  27)  it  was  held 
that  fences  built  to  the  canal  edge  and  a  wire  gate  on  the  banks 
was  not  an  unreasonable  obstruction  of  the  easement.  It  was 
also  held  that  gates  %  mile  apart  were  not  an  unreasonable 
obstruction,  but  that  many  gates  might  be. 

On  the  older  systems,  particularly  cooperative  companies, 
patrolling  was  less  frequent  than  on  present  larger  canals  and 
fences  with  gates  were  usually  permitted  at  roads.  This  served 
to  keep  road  stock  from  the  farmer's  fields  and  avoided  the  need 
of  fencing  the  right  of  way.  On  newer  and  larger  systems  where 
patrolling  is  more  regular  and  all  deliveries  are  made  by  the  ditch 
riders,  the  opening  and  closing  of  fence  gates  is  more  of  an  incon- 
venience and  such  companies  usually  limit  fencing  across  the 
canal  as  much  as  possible.  The  question  of  fences  is  often  made 
a  part  of  the  agreement  in  purchasing  rights  of  way,  when  conces- 
sions are  made  by  the  canal  owner  as  to  fences  across  the  canal, 
a  more  reasonable  price  may  be  accepted  by  the  land  owner  for 
the  right  of  way.  As  a  suitable  fence  may  cost  from  $75  to 
$125  per  mile,  the  cost  of  fencing  both  sides  of  a  narrow  right  of 
way  may  be  a  large  proportion  of  the  value  of  the  land.  A  50- 
foot  right  of  way  contains  about  6  acres  per  mile.  The  cost  of 
fencing  both  sides  at  $100  per  mile  of  fence  will  be  equivalent  to 
a  cost  of  $33  per  acre  of  land  used. 

There  is  no  fixed  practice  in  regard  to  fencing  canal  rights  of 
way.  Gates  on  the  bank  are  cheaper  than  to  fence  the  right  of 
way  and  where  cross-fences  are  not  required  too  closely  together 
the  trouble  in  using  them  may  not  justify  the  cost  of  fencing. 
Where  grazing  of  the  right  of  way  is  desired,  fencing  wall  be 
required  to  protect  the  fields  unless  herding  is  practiced.  Where 
canals  pass  through  open  range,  it  may  be  desirable  to  fence  the 
canal  as  a  protection  from  the  crossing  of  stock  and  injury  to  the 
banks.  For  small  holdings  fences  along  the  canal  may  be  pref- 
erable to  frequent  gates.  Such  fences  may  be  built  either  by 
the  land  owner  or  the  canal  owner  or  as  partition  fences  by  both, 
depending  on  which  party  receives  the  benefit  or  desires  the 
fence. 

The  U.  S.  Reclamation  Service  has  generally  been  more  strict 
than  other  companies  in  the  enforcement  of  their  regulatinos 
regarding  fences  across  canals.  In  1913  a  committee  of  the 
northern  division  recommended  that  no  fences  be  allowed  across 
canals  with  a  capacity  of  over  40  second-feet.  Where  not  con- 


46  IRRIGATION  SYSTEMS 

sidered  harmful,  the  "Use  Book"  of  the  service  states  they  should 
be  built  under  a  revocable  permit,  the  land  owner  agreeing  to 
remove  the  fence  on  demand  by  the  service.  On  some  projects 
gates  are  generally  permitted  where  ditches  leave  public  roads. 

Legal  Fences. — The  questions  which  arise  in  regard  to  the 
damage  to  crops  by  stock  have  led  the  Western  States  to  pass 
statutes  defining  liability  for  such  damages  and  specifying  the 
character  of  fences  which  are  considered  adequate.  The  same 
requirements  as  to  legal  fences  for  farms  would  probably  hold  in 
questions  involving  the  breaking  through  canal  fences  by  stock. 
The  definitions  of  legal  fences  vary  in  the  different  States.  One 
or  more  types  and  kind  of  fences  are  usually  given  as  standard 
and  a  general  requirement  inserted  that  fences  of  any  other  kind 
must  be  of  equivalent  strength  and  height.  Barb-wire  fences 
are  more  usually  specified,  the  different  States  requiring  three  to 
four  wires,  a  height  of  4  or  4J^  feet,  posts  3  to  5  inches  in  di- 
ameter set  20  to  24  inches  into  the  ground  and  spaced  12  to  80 
feet.  For  distances  between  posts  of  over  12  feet,  stays  are 
usually  required  from  8  to  10  feet  apart.  In  most  States,  the 
owner  of  land  within  a  legal  fence  can  recover  from  the  owner  of 
stock  if  the  stock  break  through  the  fence  and  cause  damage; 
if  the  fence  does  not  satisfy  the  legal  requirements,  such  recovery 
cannot  be  made.  Several  States  also  have  statutes  either  making 
it  a  misdemeanor  to  leave  gates  open  or  making  the  one  leaving 
the  gate  open  liable  for  any  damage  that  may  result.  For  parti- 
tion fences  it  is  usual  to  require  the  cost  to  be  borne  half  and  half 
by  the  adjacent  owners  provided  both  secure  benefit  from  it. 
Where  one  owner  does  not  have  the  remainder  of  his  land  fenced, 
he  is  not  required  to  pay  a  part  of  the  cost  of  the  partition  fence 
until  he  fences  the  other  sides  of  his  land  and  derives  benefit  from 
the  fence. 

Cost  of  Fences. — The  cost  of  fences  depends  on  the  character 
of  the  fence  and  the  local  conditions.  The  figures  in  Table  III 
'are  the  results  of  investigations  in  North  Dakota  by  the  U.  S. 
Department  of  Agriculture.  While  for  other  localities  the  price 
may  vary  due  to  local  costs  of  posts,  wire  or  labor,  the  figures 
given  should  furnish  a  basis  of  relative  costs  for  the  different 
types  of  fences. 

On  the  North  Platte  project  53  miles  of  4- wire  fence  are  re- 
ported to  have  cost  $75  per  mile  for  materials  and  $50  per  mile 
for  labor.  On  the  Yolo  Water  &  Power  Co.'s  system  in  Cali- 


GENERAL  MAINTENANCE 


47 


TABLE  III. — AVERAGE  COST  OF  FENCES  IN  NORTH  DAKOTA   INVESTIGATIONS 
OF  U.  S.  DEPARTMENT  OF  AGRICULTURE 


Distance   between 
posts,  rods 

Number  of  barbed 
wires 

Cost  per  rod 

Cost  per  mile 

1 

2 

$0.32 

$103 

1 

3 

0.37 

118 

in 

3 

0.29 

93 

iX 

4 

0.34 

107 

2 

3 

0.25 

81 

2 

4 

0.30 

96 

2H 

3 

0.23 

74 

2H 

4 

0.27 

89 

3 

3 

0.22 

69 

3 

4 

0.26 

83 

3 

5 

0.30 

96 

fornia  13  miles  of  woven-wire  fence  with  posts  1  rod  apart  cost 
SI. 03  per  rod  or  $330  per  mile,  about  60  per  cent,  of  which  was 
for  material.  A  26-inch  woven-wire  hog  fence  with  three  barbed 
wires  above  can  be  built  for  about  $200  per  mile  if  posts  are 
spaced  2  rods  apart.  In  building  laterals  where  fences  must  be 
removed  and  replaced  during  construction,  a  usual  contract  price 
for  such  work  is  40  cents  per  rod  for  woven-wire  and  20  cents  per 
rod  for  common  two-  or  three-wire  fences. 


REFERENCES  FOR  CHAPTER  I 

Irrigation,  Chapter  XI,  Vol.  5,  13th.  U.  S.  Census. 

Fifteenth  Annual  Report,  U.  S.  Reclamation  Service,  1915-16. 

Operation  Expenses  of  California  Irrigation  Companies,  Journal  of  Elec- 
tricity, Power  and  Gas,  Sept.  9,  1916. 

WAYMAN,  W.  M. — Damage  Claims  and  Methods  of  Handling,  1911,  First 
Conference  of  Operating  Engineers,  Boise,  Idaho. 

WIEL,  S.  C.— Water  Rights  in  the  Western  States,  1911,  Bancroft- Whitney 
Co.,  San  Francisco. 

STOCKTON,  R.  S. — Priming  and  Operating  an  Irrigation  System,  1909, 
Operation  and  Maintenance  Conference,  Powell,  Wyo. 

MITCHELL,  L.  H. — Maintenance  of  Relatively  Large  Canals  Through  Un- 
stable Geologic  Formation,  1911,  Operation  and  Maintenance  Confer- 
ence, Helena,  Mont. 

BURKY,  C.  R. — Maintenance  Problems,  1914,  Third  Conference  of  Operating 
Engineers,  Boise,  Idaho. 

MINER,  J.  H. — Reduction  of  Seepage  Losses  in  a  Canal  Through  Porous 
Shale,  Reclamation  Record,  December,  1916. 


48  IRRIGATION  SYSTEMS 

PESMAN,  O.  P. — Maintenance  of  Distribution  System,  1911,  Operation  and 

Maintenance  Conference,  Helena,  Mont. 
HEINZ,   J.   G. — Canal    Lining   Experience,    1914,    Proceedings    of    Second 

Washington  Irrigation  Institute. 
ALLISON,  J.  C. — Maintenance  of  Canals  Subject  to  Silt,- Engineering  Record, 

Nov.  16,  1912. 

CARBERRY,  R.  S. — Annual  Reports,  Imperial  Water  Co.,  No.  1. 
WAYMAN,  W.  M. — Methods  of   Combating   Weeds,  Moss  and  Burrowing 

Animals  in   Irrigation   Canals,    1911,   First   Conference  of  Operating 

Engineers,  Boise,  Idaho. 
BLISS,  G.  H. — Prevention  and  Eradication  of  Weeds  and   Moss  in  Canals 

and  on  Canal  Banks,  1913,  Second  Conference  of  Operating  Engineers, 

Boise,  Idaho. 

Method  of  Eradicating  Moss  and  Willows  on  Bear  River  Canal,  Reclama- 
tion Record,  December,  1913. 
DIBBLE,  B.  AND  PARRY,  T.  W. — Control  of  Moss  Weeds  and  Willows  on 

the  Minidoka  Project,  1917,  Sixth  Conference  of  Operating  Engineers, 

Boise,  Idaho. 
DILLMAN,  A.  C. — Grasses  for  Canal  Banks  in  Western  South  Dakota,  1913, 

Circular  115,  Bureau  of  Plant  Industry,  U.  S.  Department  of  Agriculture. 
ADAMS  AND  HUNTER. — Control  of  Tumbling  Mustard,  Popular  Bulletin  89, 

1915,  Washington  Agricultural  Experiment  Station,  Pullman,  Wash. 
Sheep  Clean  Irrigation  Ditches,  Pacific  Rural  Press,  Oct.  2,  1915. 
McGEORGE,  W.  T. — Fate  and  Effect  of  Arsenic  Applied  as  a  Spray  on  Weeds, 

Journal  of  Agricultural  Research,  Dec.  13,  1915. 

COE,  H.  S.— Weeds,  1914,  Bulletin  150,  South  Dakota  Agricultural  Experi- 
ment Station,  Brookings,  S.  D. 
BOLLEY,  H.  L.— Weeds  and  Methods  of  Eradication,   1908,   Bulletin  80, 

North  Dakota  Agricultural  Experiment  Station,  Agricultural  College, 

North  Dakota. 
Cox,  H.  R.— Weeds:  How  to  Control  Them,  1915,  Farmer's  Bulletin  660, 

U.  S.  Department  of  Agriculture. 

GRAY,  G.  P. — Herbicide  Investigations,  Monthly  Bulletin  California  Com- 
mission of  Horticulture,  April,  1916,  Sacramento,  Cal. 
HALTOM,  A.  J. — Use  of  Sheep  and  Goats  for  Cleaning  Banks  of  Canals  and 

Laterals  on  the  Salt   River   Project,    Arizona,    Reclamation   Record, 

June,  1916. 
WEISS,  A. — Protection  of  Sandy  Canal  Banks  from  Erosion,  North  Platte 

Project,  Reclamation  Record,  September,  1913. 
Biological  Survey,  U.  S.  Department  of  Agriculture,  North  American  Fauna 

No.  32,  Muskrats;  No.  39,  Pocket  Gophers. 
LANTZ,  D.  E. — Directions  for  Destroying  Pocket  Gophers,  1908,  Circular 

52,  Biological  Survey,  U.  S.  Department  of  Agriculture. 
BAILEY,   V. — Harmful  and   Beneficial   Mammals   of  Arid   Interior,    1908, 

Farmer's  Bulletin  335,  U.  S.  Department  of  Agriculture. 
MERRIAM,  C.  H. — California  Ground  Squirrels,  1910,  Circular  76,  Biological 

Survey,  U.  S.  Department  of  Agriculture. 
BURNETT,  W.  L. — Ground  Squirrels,  Circulars  9  and  14,  and  Pocket  Gophers, 

Circular  10,  Colorado  State  Entomologist,  Fort  Collins,  Colo. 


GENERAL  MAINTENANCE  49 

SPAULDING,  M.  H. — Control  of  Prairie  Dogs  and  Ground  Squirrels,  1912, 
Circular  20,  Montana  Agricultural  Experiment  Station,  Bozeman, 
Mont. 

BELL  AND  PIPER. — Extermination  of  Ground  Squirrels,  Gophers  and  Prairie 
Dogs  in  North  Dakota,  1915,  Circular  4,  North  Dakota  Agricultural 
Experiment  Station,  Agricultural  College,  North  Dakota. 

SHAW,  W.  T. — Ground  Squirrel  Control,  1916,  Popular  Bulletin  99,  Wash- 
ington Agricultural  Experiment  Station,  Pullman,  Wash. 


CHAPTER  II 

MAINTENANCE  OF  IRRIGATION  SYSTEMS 
MAINTENANCE  OF  STRUCTURES 

Available  data  regarding  the  actual  cost  of  maintenance  of 
different  types  of  structures  is  very  limited.  Such  figures  as 
have  been  made  public  vary  to  a  considerable  extent.  Repairs 
may  be  made  promptly  when  first  needed  giving  a  relatively 
uniform  cost  from  year  to  year  or  maintenance  may  be  neglected 
until  the  total  cost  of  repairs  becomes  a  large  proportion  of  the 
first  cost  or  until  replacement  is  needed.  In  the  first  years  of 
the  use  of  a  structure  repairs  to  the  material  of  the  structure 
should  be  small  in  amount  although  the  repairs  to  the  adjacent 
canal  such  as  those  due  to  erosion  or  settlement  may  be  high. 
Repairs  to  the  material  of  the  structure  will  increase  with  the 
length  of  its  use  until  a  point  is  reached  where  the  annual  cost 
of  repairs  and  greater  risk  in  use  of  the  old  structure  make  re- 
placement desirable.  This  element  of  risk  cannot  be  given  a 
definite  value  so  that  no  complete  numerical  basis  for  such  re- 
placements can  be  formulated,  the  decision  in  each  case  depends 
on  the  extent  of  the  risk,  the  damage  that  would  result  from 
failure  and  the  financial  condition  of  the  canal  owner.  Re- 
placements of  structures  will  usually  have  a  greater  cost  than 
the  original  construction  as  the  old  structure  must  be  removed 
and  the  excavation  usually  made  by  hand. 

The  annual  cost  of  repairs  of  structures  can  best  be  expressed 
as  a  percentage  of  the  first  cost.  For  canal  maintenance,  costs 
are  most  conveniently  expressed  in  terms  of  cost  per  mile  of 
canal.  For  wood  structures,  the  cost  of  repairs  to  the  structure 
itself  should  be  very  small  for  the  first  one-fourth  of  its  life, 
increasing  with  its  age  and  becoming  possibly  10  per  cent,  of  the 
first  cost  per  year  during  the  last  years  of  use.  In  some  cases 
the  total  cost  of  repairs  to  wood  structures  during  their  life  has 
equalled  the  first  cost.  Such  structures  as  checks  and  turn- 
outs may  have  a  higher  cost  of  maintenance  than  flumes  on  some 
systems;  on  others,  particularly  for  bench  flumes  or  those  set 

50 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       51 


on  poor  foundation  material,  the  reverse  may  be  true.  Wood 
pipe  under  conditions  suited  to  its  use  will  usually  have  a  lower 
maintenance  cost  than  other  wood  structures. 

Maintenance  costs  of  concrete  and  steel  in  irrigation  are  not 
available.  This  is  due  to  the  relatively  short  time  such  material 
has  been  extensively  used.  Where  such  materials  are  properly 
adapted  to  the  conditions  of  use  the  cost  of  repairs  should  be 
relatively  low.  There  is,  however,  always  the  liability  of 
mechanical  injuries  such  as  the  frost  heaving  of  concrete  linings 
or  cracking  due  to  settlement  which  will  make  repairs  necessary. 
For  steel,  protective  coatings  may  be  required  at  intervals.  In 
comparing  such  more  permanent  construction  with  wood  the 
relative  cost  of  maintenance  is  an  important  element  in  de- 
termining the  relative  first  cost  at  which  the  two  types  of  struc- 
tures will  give  an  equal  annual  cost  of  service.  It  is  not  safe  to 
assume  that  there  will  be  no  cost  for  repairs  to  the  more  per- 
manent material  although  the  actual  cost  will  be  less. 

The  following  general  figures  have  been  extracted  from  the 
reports  of  various  canal  companies  and  the  opinions  of  operating 
officials.  Relatively  wide  variations  in  cost  are  found  on  dif- 
ferent systems;  the  figures  given  represent  only  general  averages 
and  while  probably  relatively  approximate  as  between  different 
types  of  conditions  will  not  furnish  a  criterion  as  to  the  costs 
to  be  expected  on  any  single  system.  For  wood  structures  the 
annual  cost  of  maintenance  to  be  expected  may  be  taken  as 
shown  in  Table  IV. 

TABLE  IV. — ANNUAL  COST  OF  MAINTENANCE  IN  PER  CENT.  OF  FIRST  COSTS 


Period  of  use 

Wood 
flumes 

Wood 
pipe 

Wooden 
structures 

First  one-fourth  of  serviceable  life.  .  . 

Oto2 

0  to  1 

0  to  3 

Second  one-fourth  of  serviceable  life. 

1  to  3 

1  to  3 

1  to  4 

Third  one-fourth  of  serviceable  life. 

2  to  5 

1  to  4 

2  to  6 

Fourth  one-fourth  of  serviceable  life. 

3  to  8 

2  to  6 

3  to  8 

For  concrete  structures,  the  cost  of  maintenance  is  more 
largely  that  of  the  adjacent  canals.  The  cost  does  not  vary  with 
the  life  of  the  structure  as  with  wood.  In  many  cases  after 
the  first  year's  use  the  cost  of  maintenance  may  be  very  low.  For 
the  life  of  concrete  structures  the  annual  cost  of  maintenance 
may  be  taken  as  usually  varying  from  0  to  2  per  cent,  of  the  first 


52  IRRIGATION  SYSTEMS 

cost.  For  steel  structures  such  as  pipes  or  flumes  the  cost  of 
maintenance  may  be  assumed  as  varying  from  1  to  3  or  4  per 
cent,  of  the  first  cost  per  year,  consisting  largely  of  the  cost  of 
protective  coatings. 

SERVICEABLE  LIFE  OF  IRRIGATION  STRUCTURES 

The  life  of  any  structure  depends  fully  as  much  on  the  condi- 
tions of  its  use  as  on  the  material  of  which  it  is  made.  It  may 
be  necessary  to  use  a  material  under  conditions  unfavorable  to 
its  long  life  and  its  early  decay  can  be  considered  the  fault  of 
the  conditions  of  use  or  possibly  of  poor  judgment  in  selecting 
the  material,  rather  than  the  fault  of  the  material  itself.  Wood 
which  is  either  continuously  wet  or  continuously  dry  will  decay 
slowly.  The  conditions  least  favorable  for  the  long  life  of  wood 
structures  are  those  where  it  may  be  alternately  wet  and  dry. 
Decay  in  wood  is  considered  to  be  due  to  a  vegetable  growth 
which  requires  water,  air  and  heat.  In  wood  which  is  continu- 
ously wet,  air  is  lacking.  Extreme  cold,  while  retarding  the 
action  of  decay,  will  not  entirely  prevent  it. 

Concrete  should  have  an  indeterminate  life  unless  used  where 
it  is  subject  to  the  action  of  certain  alkalis  or  accidental  injury. 
The  life  of  steel  depends  more  largely  on  the  care  used  in  main- 
taining protective  coatings. 

Wood  Structures. — In  general  the  wood  structures  used  in 
irrigation  can  be  divided  into  three  classes:  (1)  wood  flumes 
where  the  material  is  not  in  contact  with  the  ground;  (2)  wood 
pipe  where  the  water  is  under  more  or  less  pressure  and  the  wood 
may  or  may  not  be  continuously  wet;  and  (3)  ordinary  wood 
structures  where  the  material  is  more  or  less  directly  in  contact 
with  the  earth.  The  lower  portions  of  the  trestles  and  the  ends 
of  wood  flumes  may  be  considered  with  class  (3).  The  dif- 
ference in  the  conditions  of  use  affects  the  durability  of  the 
structures  in  these  three  classifications. 

Life  of  Wood  Flumes. — The  life  of  wood  flumes  depends  on 
the  kind  of  material  used,  conditions  of  use  and  character  of 
construction.  As  these  conditions  vary  on  different  systems, 
the  life  of  wood  flumes  as  reported  by  different  users  varies 
widely.  A  rigidly  built  flume  having  little  leakage  will  outlast 
one  less  strongly  built.  Poor  footings  which  settle  and  cause 
leakage  will  shorten  the  life  of  a  flume.  The  thickness  of  the 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       53 

flume  lining  also  affects  the  length  of  service.  Various  protective 
coatings  or  even  relining  the  flume  box  are  used  to  increase  the 
life. 

The  period  of  serviceable  life  which  can  be  expected  from  flumes 
for  usual  conditions  will  not  exceed  20  years  for  redwood  or 
cedar,  12  to  15  years  for  fir,  and  8  to  10  years  for  pine.  These 
figures  apply  to  the  portions  of  the  flume  not  in  contact  with  the 
ground  and  are  as  long  a  life  as  can  be  expected  under  general 
favorable  conditions.  Some  flumes  have  been  used  for  periods 
longer  than  those  given,  but  the  annual  cost  of  repairs  in  the 
later  years  of  use  or  the  uncertainty  of  service  will  generally  make 
such  use  undesirable.  The  life  of  small  flumes  is  generally  less 
than  that  of  large  ones  due  to  the  less  continuous  use  of  many 
flumes,  on  sublaterals.  Flumes  used  intermittently  on  farms 
will  have  a  shorter  life  than  on  laterals  operated  continuously. 
Bench  flumes  or  flumes  set  in  contact  with  or  near  the  ground 
usually  have  a  shorter  life  than  well-built  higher  flumes.  For 
unfavorable  conditions  the  life  of  flumes  may  not  be  over  one- 
half  that  given.  Some  redwood  flumes  have  been  in  use  for  25 
years  in  California,  the  relatively  long  operation  season  and  rains 
during  the  remainder  of  the  year  keeping  them  continuously 
moist.  Others  have  been  replaced  after  15  years,  the  chief 
difficulty  being  with  the  rotting  of  the  butt  joints  at  the  end  of 
the  lining  plank  and  of  the  yokes  behind  them.  Well-constructed 
fir  flumes  on  the  Hedge  canal  in  Montana  having  3-inch  T  &  G 
siding  were  replaced  in  12  to  14  years.  Small  pine  flumes  have 
not  lasted  over  4  or  5  years  in  some  cases. 

Life  of  Wood-stave  Pipe. — The  life  of  wood-stave  pipe  varies 
more  widely  than  that  of  wood  flumes  as  it  is  more  dependent 
upon  the  conditions  of  service.  Under  favorable  conditions,  the 


TABLE  V. — LIFE  OF  WOOD-STAVE  PIPE 


Kind  of  wood 

Condition  of  use 

Average  life  in 
years 

Fir 

Uncoated  buried  in  tight  soil 

20 

Fir  

Uncoated,  buried  in  loose  soil.  ... 

4  to  7 

Fir  

Uncoated  in  air  

12  to  20 

Redwood  

Uncoated,  buried  in  tight  soil  loam  or  sand 

and  gravel  

over  25 

Fir 

\Vell-coated  buried  in  tight  soil 

25 

Fir  

Well-coated,  buried  in  loose  soil 

15  to  20 

54  IRRIGATION  SYSTEMS 

life  of  wood  pipe  should  exceed  that  of  flumes;  under  unfavorable 
conditions,  it  may  be  quite  short.  Wood  used  in  pipes  comes 
into  more  direrct  comparison  with  other  materials  than  does  wood 
used  in  flumes  and  the  results  with  its  use  have  been  more  closely 
observed.  Table  V  prepared  by  Mr.  D.  C.  Henny  and  printed 
in  the  Reclamation  Record  of  August,  1915,  summarizes  the 
data  collected  from  a  large  number  of  installations. 

The  following  general  conclusions  were  also  given: 

"(a)  Under  favorable  conditions  of  complete  saturation,  fir 
well-coated  may  have  the  same  life  as  redwood  uncoated. 

"(b)  Either  kind  of  pipe  will  have  a  longer  life  if  well-buried  in 
tight  soil  than  if  exposed  to  the  atmosphere.  Such  life  may  be 
very  long,  30  years  or  over,  if  a  high  steady  pressure  is  maintained. 

"  (c)  Either  kind  of  pipe  will  have  a  longer  life  if  exposed  to  the 
atmosphere  than  if  buried  in  open  soil,  such  as  sand  and  gravel 
and  volcanic  ash,  provided  in  a  hot  and  dry  climate  it  be  shaded 
from  the  sun. 

"(d)  Under  questionable  conditions,  such  as  light  pressure  or 
partially  filled  pipe,  fir  even  if  well-coated  may  have  only  one- 
third  to  one-half  the  life  of  redwood. 

"(e)  Under  light  pressure  the  use  of  bastard  staves  should  be 
avoided. 

"(/)  The  use  of  wooden  sleeves  in  connection  with  wire-wound 
pipe  is  objectionable  and  has  caused  endless  trouble  and  expense. 

"(g)  If  wooden  sleeves  are  employed  they  should  be  provided, 
at  least  for  sizes  from  10  inches  up,  with  individual  bands  to 
permit  taking  up  leaks." 

These  results  indicate  the  importance  of  the  character  of  the 
backfill.  If  porous  soils  into  which  air  penetrates  easily  are  used, 
the  benefits  of  covering  are  lost,  with  the  added  disadvantage 
that  inspection  cannot  be  readily  made.  A  covering  of  heavy 
soil,  3  to  4  feet  in  depth,  which  maintains  more  constant  moisture 
conditions  and  excludes  air,  gives  the  best  results.  The  pipe 
should  be  kept  full  of  water  if  a  long  life  is  to  be  secured.  The 
upper  portions  of  siphons,  which  may  be  only  partly  filled,  have 
been  found  to  have  a  shorter  life  than  the  parts  under  greater 
pressure.  The  water,  when  under  pressure,  maintains  a  more 
uniform  moisture  condition  in  the  staves,  a  condition  also  more 
easily  secured  if  the  thickness  of  the  staves  is  no  greater  than 
required  for  strength.  Cuts  from  the  butts  of  trees,  being  denser, 
are  considered  to  have  longer  life  than  top  cuts.  The  life  of  the 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       55 

pipe  is  usually  determined  by  the  life  of  the  staves.  Certain 
chemical  conditions  in  the  soil,  such  as  the  presence  of  some 
alkalis  or  of  acids  from  decaying  vegetation  may  result  in  a 
shorter  life  for  the  bands  than  for  the  staves.  For  such  locations 
it  is  preferable  to  place  the  pipe  above  ground  and  free  from  such 
action. 

Wood  pipe  is  often  coated,  particularly  the  smaller  machine- 
banded  pipe.  The  coating  on  these  is  applied  by  running  the 
pipe  through  a  bath  of  warm  asphaltum  pitch.  The  pipe  is  then 
rolled  in  sawdust  to  preserve  the  outside  coating  and  make 
handling  easier.  On  large  pipes  an  application  of  gas  tar  followed 
by  one  or  more  coats  of  refined  coal  tar,  is  often  used.  A  mixture 
of  asphaltum  and  tar  has  also  been  used.  These  are  applied  to 
the  finished  pipe  before  it  is  put  under  pressure.  It  is  difficult 
to  secure  adherence  to  wet  wood,  particularly  with  oil  paints. 
In  general  it  appears  that  the  use  of  a  coating  is  preferable  for 
buried  pipe  in  dry  porous  soil  and  possibly  on  all  buried  pipes, 
although  the  added  benefit  may  be  small  for  pipe  buried  in  heavy 
moist  soils  free  from  vegetable  matter.  Above  ground  the  value 
of  the  coating  is  more  uncertain.  For  the  protection  of  the  bands 
on  exposed  pipes  paints  similar  to  those  used  on  structural  steel 
may  be  used. 

Life  of  Wood  Structures. — The  conditions  of  use  for  the  usual 
wood  structures  are  not  as  favorable  as  for  wood  flumes  or  pipes. 
Parts  of  the  structure  may  be  continuously  wet,  parts  alternately 
wet  and  dry  and  parts  continuously  dry.  The  cutoff  walls  and 
other  substructure  may  outlast  one  or  more  renewals  of  the 
superstructure.  Heavy  well-built  structures  will  have  longer 
life  than  light  ones  due  to  the  longer  time  required  to  cause  the 
complete  decay  of  the  thicker  material  as  well  as  to  the  greater 
resistance  to  injury  offered  by  the  stronger  structures. 

Under  favorable  conditions  irrigation  structures  built  of 
redwood  or  cedar  may  have  a  useful  life  of  as  high  as  20  years; 
for  average  conditions  the  average  life  is  about  12  years  and  in 
some  cases  as  low  as  8  years.  It  is  longest  in  the  larger  and 
heavier  structures  such  as  have  been  used  on  some  of  the  earlier 
systems  in  California.  Some  of  these  have  actually  been  in  use 
for  over  25  years.  It  is  shortest  in  regions  of  high  temperature 
where  the  wood  is  both  damp  and  heated  at  depths  of  from  1  to 
2J^  feet  below  the  surface.  At  lower  depths  the  heat  is  not 
sufficient  to  make  decay  as  rapid;  nearer  the  surface  the  structure 


56  IRRIGATION  SYSTEMS 

is  dryer.  Small  redwood  structures  have  required  replacement 
after  5  years  in  such  locations.  Structures  built  of  fir  have  a 
life  varying  from  a  usual  maximum  of  15  years  to  a  usual  mini- 
mum of  6  years  with  an  expected  life  under  usual  conditions  of  8 
to  10  years.  Where  pine  is  used,  structures  will  not  generally 
last  over  10  years  and  may  not  last  over  5  years;  under  usual 
conditions  a  life  of  6  to  8  years  is  to  be  expected.  Structures 
will  usually  have  a  longer  life  in  heavy  soils  than  in  those  in  which 
the  air  has  greater  access  such  as  sands  or  gravels. 

Life  of  Concrete  Structures. — Considered  as  a  material,  con- 
crete is  practically  permanent.  There  has  been  some  injury 
from  the  action  of  certain  forms  of  alkali  but  the  injuries  to 
concrete  structures  are  much  more  generally  those  due  to  under- 
cutting or  other  accidents  in  use  rather  than  to  any  disintegra- 
tion of  failure  of  the  material  similar  to  the  failure  of  wood  struc- 
tures due  to  decay.  Concrete  has  not  been  in  use  in  irrigation 
sufficiently  long  to  secure  data  on  its  rate  of  depreciation.  De- 
preciation estimates  which  have  been  used  in  valuations  have 
been  based  on  estimated  obsolescence  or  mechanical  injury  rather 
than  on  actual  deterioration  of  the  structure.  In  a  few  in- 
stances resurfacing  has  been  required;  such  cases  have  generally 
been  due  to  lack  of  care  in  the  original  construction  rather  than 
to  actual  abrasion.  Structures,  such  as  linings  or  retaining 
walls,  may  fail  due  to  excess  pressure  behind  them ;  such  failures 
are  not  due  to  the  material  of  the  structure  itself  but  to  faults 
in  drainage  or  design.  Winter  operation  may  cause  injury  in 
the  opening  of  frozen  gates  or  in  the  breaking  of  side  walls. 

The  examples  of  injury  from  the  action  of  alkali  while  scattered 
have  in  some  cases  been  important.  There  is  still  need  for  further 
knowledge  as  to  the  details  of  such  action  and  the  methods  of 
its  prevention.  Injury  is  caused  by  the  seepage  into  the  con- 
crete of  alkali  water,  the  sulphates,  particularly  magnesium  and 
sodium  sulphate,  being  the  most  harmful.  With  some  salts 
no  harmful  action  may  occur.  The  best  remedy  is  prevention 
which  can  be  secured  most  practically  by  using  a  dense  well- 
mixed  and  faced  concrete  which  reduces  the  absorption  of  the 
alkali  water  to  a  minimum.  The  conclusions  of  the  U.  S.  Bureau 
of  Standards  based  on  the  observations  of  the  first  year's  tests 
with  concrete  drain  tile  exposed  to  alkali  in  a  number  of  localities 
are  that  tile  not  leaner  than  a  1  to  3  mixture  are  apparently  un- 
affected structurally  when  exposed  for  1  year  in  operating  drains 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       57 

in  very  concentrated  alkali  soils.  Leaner  mixtures  are  not 
generally  recommended  although  in  some  cases  tile  of  1  to  4 
mixture  were  not  affected  at  the  end  of  1  year. 

To  overcome  or  reduce  the  effect  of  low  temperatures  on  con- 
crete, the  surfaces  have  been  treated  with  waterproofing  solu- 
tions on  the  Strawberry  Valley  project.  This  was  applied  to 
structures  on  which  surface  disintegration  had  already  begun. 
Vertical  surfaces  were  treated  with  alum  and  soap  solution  and 
horizontal  surfaces  with  paraffine.  The  surfaces  were  thoroughly 
dried  and  cleaned  before  treatment.  The  alum  solution  con- 
sisted of  2  ounces  of  alum  to  1  gallon  of  hot  water.  The  soap 
solution  consisted  of  %  pound  of  castile  soap  dissolved  in  1 
gallon  of  hot  water.  The  alum  solution  was  applied  at  a  tem- 
perature of  100°F.  and  worked  in  with  brushes,  the  soap  solu- 
tion being  similarly  applied  while  the  surface  was  still  moist. 
In  some  cases  additional  coats  were  given.  One  gallon  of  alum 
solution  and  %  gallon  of  soap  solution  were  sufficient  to  give 
two  coats  to  50  square  feet.  The  cost  of  treating  24,000  square 
feet  varied  from  $0.41  to  $1.28  per  100  square  feet  and  averaged 
$0.76.  Alum  costs  18  cents  and  soap  12%  cents  per  pound. 

For  horizontal  surfaces,  the  paraffine  was  boiled  to  drive  off 
water,  heated  and  applied  with  a  paint  brush.  A  blow  torch 
was  used  to  force  the  paraffine  into  the  pores  by  its  heat.  The 
concrete  would  absorb  only  one  coat  of  such  treatment.  On 
4,000  square  feet  treated,  1  pound  of  paraffine  was  used  per 
11%  square  feet  of  surface.  The  cost  varied  from  $1.70  to  $3.78 
per  100  square  feet,  averaging  $2.11.  Paraffine  cost  $4.80  per 
100  pounds.  The  surfaces  treated  have  shown  no  further  dis- 
integration after  going  through  four  winters. 

Concrete  pipe  has  been  used  very  extensively  on  a  number  of 
systems  during  the  past  10  years.  With  the  present  knowledge 
of  its  construction  and  use  there  should  be  little  difficulty  in 
securing  well-made  pipe.  Such  pipe  should  have  a  relatively 
long  or  indefinite  life.  In  1907  the  Irrigation  Co.  of  Pomona 
relaid  a  line  of  8-inch  concrete  pipe  of  1  to  4  mixture  which  had 
been  laid  in  1888.  Only  7  per  cent,  of  the  joints  were  found 
to  be  perfectly  sound,  the  remainder  had  disintegrated.  General 
maintenance  of  such  pipe  lines  consists  of  draining  in  winter 
and  the  sluicing  of  deposits  which  may  form.  It  is  usual  for 
such  pipe  lines  to  operate  at  higher  velocities  than  the  canals  so 
that  deposits  of  silt  or  sand  are  not  to  be  expected.  Such  deposits 


58  IRRIGATION  SYSTEMS 

may  occur,  however,  at  the  lower  rates  of  discharge  which  may 
be  used  at  the  beginning  and  end  of  the  season.  Cracks  at  the 
joints  due  to  the  expansion  and  contraction  of  the  pipes  have 
caused  trouble  in  some  cases  where  the  range  of  temperature  is 
large  or  the  covering  of  the  pipes  porous  or  thin.  A  length  of 
life  of  30  to  40  years  has  been  used  in  valuations  of  concrete  pipe 
lines.  These  figures  are  largely  arbitrary,  however,  as  direct 
experience  has  not  extended  over  the  full  life  of  larger  concrete 
pipe.  In  common  with  other  forms  of  permanent  materials,  re- 
placements may  be  more  often  needed  due  to  changes  in  the  re- 
quirements of  use  such  as  changes  in  location  or  capacity  needed, 
rather  than  due  to  actual  deterioration  of  the  material  itself. 

Life  of  Steel. — Steel  is  used  in  irrigation  practice  in  flumes,  in 
pipes  and  in  gates.  The  development  of  steel  flumes  has  oc- 
curred within  the  past  15  years.  A  steel  flume  with  wood  sup- 
ports is  a  combination  type  of  structure.  The  trestles  and 
stringers  are  similar  to  those  used  with  wood  flumes  and  should 
have  a  useful  life  similar  to  that  of  the  same  kind  of  material 
when  used  with  wood  flumes.  Such  trestles  with  steel  flumes 
may  have  a  longer  life  than  with  wood  flumes,  if  the  leakage  with 
the  steel  flume  is  less.  The  useful  life  of  steel  flumes  has  not  been 
determined,  as  their  adoption  is  quite  recent.  Many  have  been 
built  on  the  systems  of  the  U.  S.  Reclamation  Service.  From 
observations  on  the  Boise  project  it  was  reported  at  the  Con- 
ference of  Operating  Engineers  in  1914,  that  "Of  the  flumes  built 
in  1909  practically  all  were  more  or  less  corroded.  Of  about  13 
flumes  built  in  1910,  the  majority  were  in  good  condition  but 
one  was  considerably  corroded.  Of  about  21  flumes  built  in 
1911,  two  were  considerably  corroded.  Of  about  14  flumes 
built  in  1912,  two  were  seriously  corroded."  It  was  stated  that 
there  was  no  decided  difference  between  different  makes  of  flumes. 
The  greatest  amount  of  corrosion  and  rust  appeared  to  be  along 
the  joints,  on  the  downstream  side.  It  was  recommended  that 
the  bands,  channels  or  other  parts  forming  the  joints  should  be 
galvanized  as  well  as  the  sheet  metal  of  the  flume.  In  case 
deterioration  appears,  painting  was  recommended.  In  an  article 
in  the  Reclamation  Record  for  November,  1916,  Mr.  F.  D.  Pyle 
states  that  of  several  kinds  of  paint  tried  on  the  Uncompahgre 
project  only  coal  tar  and  coal-tar  compound  paints  had  stood 
one  season's  use  and  gave  indications  of  permanence.  It  was 
also  stated  that  the  indications  on  that  system  were  that  un- 


MAINTENANCE  OF  IRRIGATION  SYSTEMS         59 

protected  galvanized-steel  flumes  will  have  a  life  of  10  or  12 
years  except  under  the  most  trying  conditions,  i.e.,  high  velocity 
of  water  carrying  sand  and  fine  gravel,'  where  the  life  in  one 
particular  instance  was  only  four  season's  use. 

The  use  of  steel  and  iron  pipe  in  irrigation  has  generally  been 
limited  to  those  conditions  of  pressure  for  which  other  types  of 
pipes  were  not  suited.  Their  use  in  irrigation  has  not  been 
sufficient  in  length  of  time  or  in  amount  to  indicate  their  probable 
useful  life  for  such  purposes.  Data,  however,  are  available 
from  use  in  mining  and  power  service.  Thin  steel  pipes,  such  as 
%  inch  in  thickness,  are  used  in  the  smaller  sizes  for  the  lighter 
pressures  in  some  distribution  systems,  particularly  with  pump- 
ing plants.  These  should  have  a  useful  life  of  15  to  25  years. 
Heavier  pipe,  ^  inch  thick,  should  last  25  to  50  years.  For  pipe 
of  the  larger  sizes,  which  can  be  recoated  during  the  portion  of  the 
year  when  they  are  not  in  use,  even  longer  life  may  be  secured. 

Due  to  the  thinness  of  the  pipe,  protective  coatings  are  rela- 
tively more  important  on  steel  pipes  than  on  those  of  other  mate- 
rial. The  more  generally  used  coatings  consist  of  some  of  the 
forms  of  tar  or  asphalt  mixtures  applied  hot,  the  smaller  pipe 
being  dipped  and  the  larger  ones  treated  in  the  field.  The  San 
Fernando  siphon  of  the  Los  Angeles  aqueduct  was  painted  inside 
and  outside  with  one  coat  of  water-gas  tar  and  two  coats  of  coal 
tar.  One  gallon  of  tar  covered  about  200  square  feet  of  pipe. 
The  Spring  Valley  Water  Co.  has  used  a  mixture  of  coal  tar  and 
natural  crude  asphaltum,  using  1,400  pounds  of  asphaltum  to  50 
gallons  of  coal  tar.  Some  of  this  coating  has  been  in  use  nearly 
50  years.  The  Pacific  Gas  &  Electric  Co.  uses  one  coat  of  Dixon's 
Graphite  Paint,  inside  and  outside  on  unburied  pipe,  repainting 
every  2  or  3  years.  In  some  cases  steel  pipe  may  be  encased  in 
concrete.  Where  steel  pipes  are  laid  in  alkali  soils  special  protec- 
tion may  be  needed,  Pipe  %e  inch  thick  has  in  some  cases  been 
corroded  entirely  through  in  3  years  where  laid  in  alkali  soil  in 
the  California  oil  fields.  On  the  Uncompahgre  project  in  Colo- 
rado a  26-inch  siphon  was  built  in  1910  in  alkali  ground  for  which 
ingot  iron  pipe  was  used.  This  was  in  good  condition  after  4 
years  use  although  some  rusting  had  occurred. 

SELECTION    OF    TYPE    OF    STRUCTURES 

The  relative  economy  of  wood  and  concrete  depends  on  many 
factors,  only  a  part  of  which  relate  directly  to  the  first  cost.  For 


60  IRRIGATION  SYSTEMS 

any  given  condition  where  the  relative  construction  and  main- 
tenance costs  and  useful  life  can  be  estimated  a  direct  comparison 
of  costs  on  an  investment  basis  can  be  made.  The  data  for  such 
estimates  can  be  secured  for  replacements.  In  new  systems,  the 
selection  may  be  based  on  other  conditions  such  as  uncertainty 
as  to  the  capacity  needed  or  the  location  of  certain  structures, 
lack  of  transportation  facilities  making  the  cost  of  cement  high, 
or  limited  financial  resources  and  high  interest  rates.  In  replace- 
ments, the  location  and  character  of  the  structures  is  more  defi- 
nitely known,  the  financial  standing  or  resources  may  make 
interest  rates  less  and  the  development  following  irrigation  may 
have  included  improved  transportation  facilities.  For  such 
conditions,  replacements  can  be  determined  more  largely  on  an 
investment  basis. 

In  concrete  structures  the  cost  of  concrete  is  usually  from  60  to 
90  per  cent,  of  the  total  cost  of  the  structure.  The  total  cost  of 
wood  similarly  varies  from  50  to  75  per  cent,  of  the  total  cost  of 
wood  structures.  For  wood  flumes,  the  cost  of  the  flume  box 
and  trestle  generally  equals  over  three-fourths  of  the  total  cost 
of  the  structure  as  a  whole.  In  similar  types  of  structures  an 
average  of  about  6.5  cubic  yards  of  concrete  are  equivalent  to 

1.000  feet  board  measure  of  lumber;  the  ratio  varies  rather  widely , 
however,  in  individual  cases.     Concrete  structures  should  have 
a  lower  cost  of  maintenance  than  those  of  wood.     If  replace- 
ments are  to  be  made  on  an  investment  basis  the  ratio  of  first 
cost  at  which  the  capitalized  cost  of  service  becomes  equal  can 
be  computed  for  various  conditions.     These  are  given  in  Fig.  4, 
for  an  assumed  life  of  40  years  for  concrete  structures  and  from 
5  to  20  years  for  wood  structures.     Sets  of  curves  are  shown  for 
interest  rates  of  6,  8  and  10  per  cent,  and  for  annual  costs  of 
maintenance  of  wood  structures  up  to  8  per  cent.     Having  the 
probable  life,  cost  of  maintenance  and  value  of  money  or  interest 
rate,  these  curves  give  the  ratio  of  cost  between  wood  and  con- 
crete at  which  they  are  equally  desirable  as  investments.     If,  for 
instance,  wood  structures  have  an  estimated  life  of  12  years,  an 
average  annual  cost  of  maintenance  of  4  per  cent.,  and  money 
can  be  secured  at  8  per  cent.,  concrete  structures  would  be  as 
economical  as  wood  structures  if  the  concrete  could  be  built  for 

2.1  times  as  much  as  wood.     If  concrete  structures  could  be 
built  for  less  than  2.1  times  the  cost  of  wood  structures,  they  would 
be  more  economical  on  an  investment  basis.     The  factors  not 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       61 

included  in  this  comparison,  such  as  greater  safety  in  operation, 
usually  enable  one  to  expend  for  concrete  something  more  than 
the  amount  indicated.  For  similar  conditions  to  the  above 
example,  except  the  interest  rate,  the  ratio  of  first  cost  would  be 
2.35  for  interest  at  6  per  cent,  and  1.85  for  interest  at  10  per  cent. 
If  the  life  of  the  wood  structure  were  only  6  years,  the  ratios 
would  be  3.4,  3.0  and  2.5  for  6,  8  and  10  per  cent,  interest  rates, 


2  3  4 

Ratios  of  First  Cost  for  Equal  Capitalized  Cost  of  Service 
For  Interest  Rate  of  6% 


8  of  Wood  Structures-Years  Life  of  Wood  Structures  -Yea 

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Figures  on  each  curve 
represent  the  estimated 
annual  cost  of  mainten. 
ance  of  wood  structures 
in  per  cent    of  the  first 
cost  of  the  structure. 

The   ratios  given    are 
the  ratios  of    first  cost 
of    wood    and    concrete 
structures  at  which  the 
capitalized  cost    of  ser- 
vice becomes    e<jttal  for 
an  assumed  life  of  con. 
Crete    structures    of    40 
years    and  for    life  and 
cost  of  annual  mainten* 
ance  of  wood  structure! 
as  shown. 

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First  Cost  for  Eqoal  Capitalized 
Cost  of  Service 
For  Interest  Rate  of  8  % 

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^Ratios  of  First  Cost  for  Equal  Capitalized  Cost  of  Service 
For  Interest  Kate  of  10% 


FIG.  4. — Comparison  of  first  costs  of  wood  and  concrete  structures  for  equal 
capitalized  cost  of  service. 


respectively.  The  smaller  increased  costs  which  one  can  afford 
to  pay  for  longer-lived  construction,  when  interest  rates  are  high, 
is  quite  noticeable.  If  the  annual  cost  of  maintenance  is  dis- 
regarded, the  ratios  for  12-year  life  become  1.8,  1.6  and  1.45  and 
for  6-year  life  2.9,  2.6  and  2.2  for  interest  rates  of  6,  8,  and  10  per 
cent.  Longer  estimated  life  for  the  concrete  structures  than  40 
years  does  not  materially  change  the  ratios.  A  shorter  life  for 


62  IRRIGATION  SYSTEMS 

the  concrete  than  40  years  reduces  the  amount  which  one  can 
afford  to  expend  for  its  construction.  If  concrete  is  estimated  to 
have  a  life  of  only  20  years,  the  ratios  will  be  reduced  from  one- 
fourth  to  one-third  from  those  given  in  Fig.  4. 

Where  the  topography  is  regular,  the  costs  of  concrete  struc- 
tures will  usually  equal  from  10  to  20  per  cent,  of  the  total  cost  of 
main  canals  and  from  25  to  40  per  cent,  of  the  total  cost  of  laterals 
or  an  average  of  20  to  35  per  cent,  of  the  cost  for  the  whole  system. 
The  similar  figures  for  wood  structures  are  about  8  to  15  per 
cent,  for  main  canals,  15  to  35  per  cent,  for  laterals,  and  10  to  25 
per  cent,  for  systems  as  a  whole.  For  irregular  or  steep  topog- 
raphy the  cost  of  the  structures  will  usually  comprise  about  one- 
half  again  as  large  a  percentage  of  the  total  cost. 

On  many  systems,  the  diversion  canal  passes  through  side-hill 
locations  in  which  the  first  cost  of  bench  flumes  may  be  cheaper 
than  for  excavated  canal  sections.  Where  enlargements  of 
earth  canals  in  such  locations  are  required  it  may  be  less  expen- 
sive to  secure  the  increased  capacity  by  concrete  lining  with 
its  lower  frictional  resistance.  For  such  conditions,  questions  of 
safety  in  operation  and  decreased  liability  of  breaks  may  be 
given  greater  weight  than  the  actual  relative  costs.  Where  wood- 
bench  flumes  have  been  used  in  original  construction,  on  some 
systems  they  have  been  replaced  with  canals  excavated  either 
entirely  in  earth  or  with  a  retaining- wall  section  on  the  lower 
bank  or  with  concrete-lined  sections.  Among  such  canals  are 
the  Bear  River  canal  in  Utah  and  the  Hedge  canal  in  Montana 
(Plate  IV,  Fig.  A).  On  the  Modesto  and  the  Turlock  systems 
in  California  a  number  of  flumes  crossing  drainage  channels  have 
been  replaced  with  lined  sections  carried  on  hydraulic  fills  (Plate 
IV,  Fig.  B),  the  drainage  being  handled  through  culverts.  There 
is  a  tendency  toward  the  use  of  such  more  permanent  construc- 
tion on  systems  which  have  passed  the  earlier  stages  of  develop- 
ment (Plate  IV,  Figs.  C  and  D).  This  is  due  to  the  better  finan- 
cial conditions  of  such  systems  and  to  the  change  in  relative  costs 
of  materials,  lumber  being  generally  higher  in  price  at  present 
than  at  the  time  many  of  these  systems  were  built. 

Wood  structures,  however,  have  the  advantage  that  they  can 
be  used  for  replacements  which  have  to  be  built  and  in  use 
quickly,  such  as  in  repairing  breaks  in  side-hill  canals  or  in  re- 
placing washed-out  structures. 


PLATE  IV. 


FIG.  A. — Side  hill  canal  with  retaining  wall  used  to  replace  wood  bench 
flume,  Hedge  canal,  Montana. 


FIG.  B. — Lined  canal  on  hydraulic  fill  used  to  replace  wood  flume,  Turlock 
Irrigation  District. 

(Facing  page  62.) 


PLATE  IV. 


FIG.  C. — Concrete  flume  in   light   fill  in  sandy   soil,    Crocker-Huffman 
Land  and  Water  Co.  California. 


FIG.  D. — Concrete  arch  flume  used  to  replace  wood  flume,  Modesto  irri- 
gation district. 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       63 

MAINTENANCE  OF  RESERVOIRS 

Reservoir  maintenance,  except  that  due  to  larger  accidents, 
is  usually  small  in  amount.  Where  the  reservoir  is  situated  on 
the  stream  channel,  the  dam  is  similar  to  those  used  for  diversion. 
Where  the  site  is  not  situated  on  a  stream  but  is  filled  through  a 
feeder  canal,  the  problems  of  spillway  capacity  are  removed 
or  very  largely  reduced.  The  maintenance  of  the  outlet  works 
is  similar  to  that  of  the  headgate  of  canals.  For  the  higher 
dams  the  erosion  in  the  outlets  and  the  operation  of  the  gates 
has  given  much  difficulty  in  some  cases.  Multiple  sets  of  gates 
at  different  elevations  are  sometimes  used  to  overcome  such 
difficulties. 

The  action  of  waves  on  the  face  of  earth  dams  may  cause  much 
trouble.  Such  dams  are  faced  on  the  water  side  with  coarse 
material  or  concrete.  On  the  Deer  Flat  reservoir,  gravel  has 
been  dumped  on  the  upper  slope  to  be  worked  down  the  slope 
by  wave  action  should  additional  protection  be  needed.  On 
the  Belle  Fourche  reservoir,  the  concrete  paving  slabs  have  in 
some  cases  moved  outward  and  slipped  downward  near  the  water 
line  due  to  the  water  pressure  behind  them.  The  water  which 
had  entered  between  the  slabs  could  not  escape  as  rapidly  as 
the  waves  receded,  so  that  its  pressure  forced  the  slabs  outward. 
This  has  been  repaired  by  keying  the  slabs  together. 

Where  dry-rock  riprap  is  used,  either  hand-laid  or  unplaced, 
heavy  wave  action  may  cause  an  undermining  of  the  paving 
which  results  in  its  settlement.  The  wave  action  washes  out 
the  finer  material  under  the  paving  in  such  cases.  This  can  be 
overcome  by  the  use  of  heavier  rock  more  carefully  laid  or  by  the 
use  of  grouted  paving  or  concrete  facing  where  heavy  wave  action 
is  expected.  The  facing  rock  should  not  be  laid  directly  on 
the  earth  slope;  an  intermediate  layer  of  smaller  rock  or  gravel 
should  be  used.  Such  riprap  has  a  much  greater  resistance  to 
wave  action. 

A  double  log  boom  with  the  logs  placed  about  3  feet  apart 
anchored  a  few  feet  from  the  water's  edge  will  reduce  erosion  due 
to  wave  action. 

Some  protection  on  the  downstream  slope  against  the  action 
of  rain  may  be  needed.  This  can  be  secured  by  the  growth  of 
vegetation  where  the  soil  and  moisture  conditions  permit  or  by 
a  gravel  or  loose  rock  layer. 


64  IRRIGATION  SYSTEMS 

In  several  of  the  States,  the  State  exercises  more  or  less  con- 
trol and  supervision  over  the  plans  and  construction  of  dams. 
While  in  general  beneficial,  such  supervision  does  not  go  as  far 
in  requiring  safe  construction  as  a  canal  system  built  on  an 
investment  basis  would  ordinarily  go  on  its  own  accord. 

MAINTENANCE  OF  DIVERSION  DAMS  AND  HEADWORKS 

Diversion  dams  are  special  structures  whose  design  depends 
on  local  conditions  which  vary  with  each  system.  Permanence 
is  more  essential  in  the  headgates  than  in  any  other  part  of  the 
system  as  injury  to  the  inlet  control  of  the  canal  may  cause  a 
loss  of  water  to  the  entire  system.  As  the  conditions  of  founda- 
tions, ice,  and  drift  which  diversion  dams  and  headgates  may 
have  to  withstand  are  difficult  to  forecast  and  to  provide  against, 
such  structures  should  be  built  only  under  technical  engineering 
advice.  If  well-designed  and  built,  such  structures  should  not 
have  high  maintenance  costs.  On  some  streams  having  large 
low-water  flows  in  proportion  to  the  amount  diverted  and  fairly 
permanent  channels,  a  diversion  dam  may  not  be  required. 
This  is  the  case  with  several' canals  diverting  from  the  Yellow- 
stone River.  The  headgates  in  such  cases  should  be  of  sub- 
stantial construction  and  planned  so  that  the  flow  past  them  is 
sufficient  for  diversion  and  that  no  cutting  of  the  canal  at  the 
headgate  will  occur. 

On  streams  having  poor  foundations  it  may  be  cheaper  to  use 
temporary  diversion  dams  during  the  low-water  period  of  each 
year.  During  high-water  periods  there  will  usually  be  little 
trouble  in  securing  the  diversion.  During  low  water,  brush  and 
sand  sacks  or  other  temporary  dams  may  be  used.  The  annual 
cost  of  such  dams  may  be  less  than  the  fixed  charges  and  main- 
tenance on  a  permanent  structure.  Such  methods  may  be  used 
during  the  earlier  years  of  a  system  while  the  amount  diverted 
is  small.  As  diversion  increases  and  as  funds  may  become 
available,  a  permanent  diversion  dam  may  be  built.  In  some 
cases  the  stream  channel  may  be  changed  during  high- water 
flow  so  as  to  throw  the  low-water  channel  away  from  the  head- 
gate.  This  can  be  controlled  by  the  diversion  dam  or  by  the 
proper  location  of  the  headgate.  Temporary  diversion  dams 
are  not  suited  to  streams  having  a  torrential  or  fluctuating  flow 
as  more  than  one  dam  may  be  required  per  season.  On  snow- 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       65 

fed  streams  there  is  less  fluctuation  in  the  low  flow  and  such 
temporary  dams  will  usually  not  be  washed  out  during  the  later 
irrigation  season.  Duplicate  control  of  the  headgates  is  de- 
sirable on  all  except  small  canals.  This  may  be  secured  by  the 
use  of  two  sets  of  gates,  so  that  in  case  of  injury  to  one  set  the 
other  set  can  be  used.  Provision  should  be  made  for  flashboard 
grooves  above  the  upper  set  to  enable  emergency  repairs  to  be 
made.  In  order  to  regulate  the  flow  into  the  canal  more  easily 
a  spillway  is  frequently  provided  just  below  the  headgate. 
Secondary  gates  below  such  spillways  will  protect  the  canal  in 
case  of  injury  to  the  upper  gate  and  give  a  closer  control  of  the 
amount  diverted.  Sand  boxes  may  be  combined  with  the 
spillway  if  there  is  need  for  their  use. 

Screens  across  headgates  serve  two  general  purposes.  One  is 
to  prevent  the  entrance  of  drift,  the  other  the  entrance  of  fish. 
The  first  type  is  desirable  from  the  point  of  view  of  canal  opera- 
tion as  such  drift  may  result  in  the  clogging  of  screens  or  checks 
to  the  injury  of  the  canal.  The  entrance  of  fish  into  the  canal 
is  not  harmful  to  the  canal;  screens  to  prevent  such  entrance 
are  required  by  law  in  many  States,,  however,  in  order  to  protect 
the  public  interest  in  the  fish. 

The  prevention  of  the  entrance  of  drift  into  a  canal  is  usually 
not  difficult.  The  proper  location  and  design  of  the  headgates 
may  prevent  drift  being  carried  to  them  when  the  amount 
diverted  is  a  minor  portion  of  the  amount  flowing  in  the  stream. 
The  drift  occurring  in  streams  consists  more  largely  of  logs  or 
debris  from  timber.  Most  of  this  can  be  kept  out  by  a  log 
boom  or  by  coarse  screens.  Where  silt  occurs  in  large  quantities 
the  prevention  of  its  entrance  requires  a  careful  design  of  the 
diversion  and  headgates,  the  principles  of  which  are  discussed 
in  a  number  of  books.  The  general  purpose  of  such  designs  is 
to  enable  the  clearer  surface  flow  to  be  taken  into  the  canals. 
Screens  used  for  drift  may  be  a  simple  log  boom  arranged  to 
divert  the  drift  away  from  the  gates  or  a  rack  screen  of  relatively 
wide  spacing.  Both  types  are  frequently  used  on  the  same 
headgate. 

In  the  majority  of  States,  the  State  official  in  charge  of  the 
administration  of  the  fish  and  game  laws  has  the  power  to 
require  screens  on  canals  when  he  considers  their  use  necessary. 
To  prevent  the  entrance  of  fish  into  a  canal  requires  screens  of 
much  closer  mesh  than  those  needed  for  other  purposes.  To 

5 


66  IRRIGATION  SYSTEMS 

hold  the  small  fish  such  as  are  planted  in  many  streams  by  the 
States  requires  a  mesh  so  small  that  fine  drift  which  would  not 
cause  damage  in  the  canal  will  be  held  on  the  fish  screen.  Such 
drift  clogs  the  screen  and  requires  constant  attention  if  the 
quantity  diverted  is  to  be  kept  constant.  While  the  prevention 
of  the  loss  of  fish  in  streams  is  certainly  desirable,  it  is  a  serious 
question  as  to  whether  it  is  practical  to  use  a  screen  sufficiently 
fine  to  prevent  their  entrance  into  canals.  This  has  been  recog- 
nized in  some  States  and  the  enforcement  of  statutes  regarding 
such  fish  screens  has  been  very  lenient.  In  California  present 
requirements  of  the  Fish  and  Game  Commission  are  for  screens 
with  3/£-inch  opening  on  streams  where  there  are  trout  and  %- 
inch  on  others.  There  are  some  60  or  70  patented  types  of  fish 
screens,  both  fixed  and  moving,  on  the  market. 

The  laws  of  several  of  the  States  also  require  that  fish  ladders 
shall  be  provided  at  all  dams  on  streams.  Various  designs  have 
been  approved  for  such  ladders  which  in  some  cases  operate 
successfully.  In  some  cases  the  fish  ladders  have  been  installed 
for  the  purpose  of  compliance  with  the  letter  of  the  law  only 
and  have  not  been  maintained  so  as  to  be  of  use.  On  dams  of 
moderate  height  or  on  streams  of  moderate  flood  flow  such  fish 
ladders  can  be  used  with  success.  On  high  dams  or  large  flood 
depths  it  is  preferable  to  recognize  that  the  dam  and  fish  develop- 
ment are  not  in  accord  and  waive  the  minor  benefit  of  the  fish 
in  favor  of  the  major  benefit  of  the  development.  In  Washington 
a  fish  hatchery  may  be  maintained  above  a  dam  as  a  substitute 
for  a  fish  ladder. 

On  large  canals  it  is  usual  to  keep  a  man  at  the  headgate  both 
for  the  purpose  of  regulating  the  amount  diverted  and  for  inspec- 
tion of  the  structures.  Such  gate  tenders  may  also  patrol  a  por- 
tion of  the  canal  below  the  headgate. 

MAINTENANCE  OF  GENERAL  STRUCTURES 

Such  general  structures  include  those  which  resist  water  pres- 
sure and  around  or  under  which  water  tends  to  force  a  passage. 
Among  such  structures  are  drops,  checks,  division  gates,  lateral 
headgates,  inlets  and  outlets  of  flumes.  The  two  principal 
sources  of  injury  in  connection  with  the  use  of  such  structures 
are  those  due  to  the  erosion  of  the  adjacent  canal  and  to  the 
undercutting  of  the  structure  itself.  Maintenance  will  also  be 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       67 

required  in  replacing  portions  which  decay  or  become  injured 
while  the  remainder  of  the  structure  is  in  serviceable  condition. 

Erosion  of  Canals  Adjacent  to  Structures. — At  any  structure 
through  which  the  water  has  a  higher  velocity  than  that  in  the 
adjacent  canal  checking  such  velocity  or  protection  to  the  canal 
must  be  used.  Both  methods  are  used,  either  separately  or  in 
combination.  The  present  tendency  of  practice  is  toward  the 
prevention  of  injury  by  means  of  overcoming  the  fall  or  velocity 
before  the  water  leaves  the  structure  so  as  to  reduce  the  amount 
of  canal  protection  needed.  The  lower  portion  of  structures 
may  be  designed  to  deliver  water  to  the  canal  below  at  normal 
cross-section  and  nearly  normal  velocity.  Various  forms  of 
stilling  basins  and  baffles  are  also  used. 

The  forms  which  will  be  assumed  by  eddy  currents  and  back- 
wash as  well  as  the  amount  of  direct  erosion  depend  on  compli- 
cated hydraulic  conditions  not  capable  of  computation.  The 
extent  of  canal  protection  required  depends  on  the  conditions  at 
the  structure  and  the  character  of  the  material ;  its  determination 
depends  on  experience  in  direct  observation  although  various 
rules  of  thumb  may  be  used  (Plate  V,  Figs.  B,  C  and  D).  The 
extent  of  the  erosion  which  will  occur  even  under  similar  condi- 
tions is  quite  variable. 

The  width  of  opening  through  checks  affects  the  extent  of 
erosion  below.  Narrow  openings  increase  the  velocity  through 
the  structure  and  also  the  irregularity  of  flow  if  more  than  one 
opening  is  used.  Narrow  openings  may  also  give  trouble  from 
clogging  with  drift. 

In  order  that  excess  cost  in  protection  may  be  avoided,  the 
amount  used  is  frequently  deficient.  Protection  against  such 
erosion  may  have  to  be  placed  with  water  in  the  canal.  This  can 
be  done  with  brush  held  with  stakes  or  rock,  by  dumping  in  loose 
rock  or  by  sand  sacks.  The  brush  can  be  bound  in  bundles  and 
weighted  with  rock  or  held  by  stakes,  or  it.  may  be  piled  behind 
wire  netting.  The  brush  used  may  be  sage  brush,  if  available, 
or  willows.  Such  work  is  of  rough  appearance  but  •  generally 
effective.  Sage  brush  will  last  several  years  when  used  in  this 
way;  it  may  be  burned  out  before  it  decays  in  the  burning  of 
weeds  unless  care  is  used  in  such  weed-control  work.  If  the  brush 
reduces  the  velocity  in  its  vicinity  to  a  sufficient  extent,  silt  may 
deposit  so  as  to  hold  the  brush  in  place. 

If  repairs  can  be  postponed  until  water  is  out  of  the  canal,  the 


68  IRRIGATION  SYSTEMS 

brush  can  be  more  carefully  placed  or  rock  can  be  hand  laid  if 
desired.  Concrete  lining  is  the  most  permanent  protection; 
it  can  be  placed  only  when  water  is  out  of  the  canal.  In  some 
cases  loose  concrete  blocks  have  been  used  in  preference  to  con- 
tinuous lining. 

Toe  walls,  located  at  the  lower  edge  of  structures  and  project- 
ing above  the  canal  grade  in  order  to  form  a  water  cushion  above 
them,  have  also  been  used.  Such  walls  result  in  disturbed  flow 
into  the  canal  below  and  a  greater  tendency  toward  erosion.  On 
some  structures  on  the  Orland  project  it  has  been  found  desirable 
to  remove  such  walls.  Water  cushions  are  preferably  constructed 
below  grade  and  the  sides  and  floor  brought  to  the  canal  section 
at  the  downstream  side. 

Where  erosion  at  structures  occurs  the  eroded  material  may  be 
deposited  in  a  canal  below  and  obstruct  the  flow  unless  the  grade 
of  the  canal  is  sufficient  to  give  a  relatively  high  velocity. 

Cutting  Around  Structures. — Water  tends  to  force  a  passage 
around  structures  due  to  the  pressure  caused  by  the  difference  in 
elevation  of  the  water  above  and  below  the  structure.  This 
tendency  is  greatest  where  the  fall  is  greatest  as  in  drops.  For 
some  structures  such  as  checks  operated  nearly  open  there  may 
be  little  drop  in  the  water  surface  and  consequently  little  pressure 
to  cause  cutting  around  the  structure.  When  water  succeeds  in 
securing  access  to  the  under  side  of  a  structure  an  upward  pres- 
sure will  be  caused  or  a  passageway  around  the  structure  will  be 
opened.  If  water  passes  the  upper  cutoff  wall  in  greater  quanti- 
ties than  are  able  to  escape  from  under  the  structure,  the  water 
beneath  the  structure  will  tend  to  have  a  pressure  due  to  the 
elevation  of  the  water  above  the  structure.  If  the  water  flowing 
through  the  structure  has  a  lower  elevation  than  that  above,  as  in 
checks  or  drops,  the  upward  pressure  may  exceed  the  downward 
load.  This  results  in  some  cases  in  the  actual  floating  out  of 
wooden  structures,  being  aided  by  the  buoyancy  of  the  material 
(Plate  V,  Fig.  A).  Such  floating  is  best  prevented  by  the  use 
of  an  adequate  cutoff  wall  at  the  upstream  side  of  the  structure. 
This  should  extend  well  into  the  bottom  and  sides  and  be  thor- 
oughly puddled.  Too  deep  a  downstream  cutoff  may  tend  to 
prevent  the  escape  of  water  getting  below  the  structure  and  cause 
an  accumulation  of  upward  pressure.  Such  downstream  cutoffs 
are  required  to  prevent  backwash  under  the  structure;  depend- 


PLATE  V. 


FIG.  A. — Light  wood  check  weighted  to  prevent  floating. 


FIG.  B. — Erosion  below  structure. 


(Facing  page  68.) 


PLATE  V. 


FIG.  C. — Erosion  below  drop,  Lateral  on  North  Platte  project,  Nebraska. 


FIG.  D. — Erosion  below  drop,  Modesto  irrigation  district. 


MAINTENANCE  OF  IRRIGATION  SYSTEMS     69 

ance  against  leakage  around  the  structure  should  be  placed  on 
the  upstream  cutoff. 

Proper  backfilling  of  structures  is  frequently  difficult  to  secure. 
On  new  construction  water  for  puddling  may  not  be  easily  se- 
cured. Tamping  of  damp  earth  can  be  made  to  give  good  results 
but  it  is  difficult  to  secure  proper  care  in  such  work. 

If  found  in  time,  washing  around  cutoffs  may  be  repaired  with- 
out material  injury  to  the  structure.  The  material  in  washed-out 
timber  structures  can  be  at  least  partially  used  again;  a  washed- 
out  concrete  structure  is  more  usually  a  total  loss.  On  small 
structures,  where  the  fall  at  the  structure  is  small,  particularly 
in  heavy  soils,  passageways  under  the  floor  or  sides  may  enlarge 
slowly  and  if  found  in  time  can  be  stopped  without  shutting  off 
the  water.  New  structures  should  be  closely  watched  in  their 
first  season  and  given  a  thorough  inspection  after  water  is  shut 
off.  Cutoffs  which  hold  during  the  first  season's  use  are  not  as 
liable  to  give  trouble  later  unless  the  quantity  of  water  carried 
is  materially  increased  or  cutting  is  started  by  some  burrowing 
animal. 

MAINTENANCE  OF  FLUMES 

Maintenance  of  flumes  consists  of  repairs  to  both  the  flume , 
and  its  supporting  trestle.  If  the  material  in  the  flume  box 
becomes  worn  and  leaky,  the  inside  may  be  lined  with  1-inch 
matched  lumber  to  give  water  tightness  depending  on  the  old 
material  for  strength,  or  with  unsurfaced  boards  and  some  of 
the  various  tar  or  asphaltic  paints.  For  smaller  flumes  tar  paper 
may  be  placed  in  the  flume.  Such  linings  are  more  generally 
needed  on  flumes  carrying  water  at  relatively  high  velocity  or 
containing  sand.  For  such  conditions  the  paper  is  not  well  suited. 

Leakage  and  in  some  cases  actual  wear  can  be  reduced  by  the 
use  of  coatings  applied  to  the  inside  of  the  flume.  A  coating 
has  been  used  on  the  Bear  River  canal  system  in  Utah  which 
consists  of  1  part  tar  and  4  parts  tar  pitch,  with  gravel  applied 
as  a  thick  coating  rolled  on  while  hot.  This  has  been  found  to 
stick  to  the  sides  and  form  a  water-tight  coat.  To  be  successful 
it  is  necessary  to  prevent  the  entrance  of  water  behind  the  coat- 
ing, as  such  moisture  causes  swelling  of  the  wood  and  cracking 
of  the  coating.  Other  coatings  used  consist  of  a  coat  of  water- 
gas  tar  followed  by  a  coat  of  coal  tar.  Various  asphaltic  prepa- 
rations have  also  been  used.  If  such  coatings  are  to  be  used 


70  IRRIGATION  SYSTEMS 

it  is  preferable  to  make  the  application  when  the  wood  is  new, 
the  adhesion  usually  being  much  closer.  On  the  Modesto 
irrigation  district  a  thin  mortar  lining  or  plaster  reinforced  with 
a  wire  mesh  has  been  used  on  the  inside  of  flumes  to  temporarily 
extend  their  lives.  The  use  of  such  coatings  may  add  to  the 
life  of  the  flume  and  reduce  maintenance  costs  due  principally 
to  the  reduction  in  leakage. 

The  repair  of  trestlework  is  more  difficult  and  expensive. 
The  members  of  the  trestle  should  be  sufficiently  heavy  to  have 
an  estimated  life  at  least  as  great  as  that  of  the  flume  box  so 
that  repairs  or  replacements  of  members  will  not  be  needed 
during  the  life  of  the  flume.  As  the  trestlework  becomes  less 
strong  due  to  age  it  may  be  strengthened  by  the  use  of  additional 
sway  and  diagonal  bracing. 

A  more  frequent  trouble  with  the  trestles  of  flumes  comes  from 
the  settling  of  footings  usually  due  to  the  softening  of  the  founda- 
tion caused  by  leakage  from  the  flume.  Such  settlement  reduces 
the  freeboard  in  the  flume  and  if  of  material  amount  reduces  the 
capacity  of  the  flume  as  well  as  endangering  its  safety.  Actual 
profiles  of  flumes  in  use  show  that  a  flume  in  which  no  part  is 
more  than  0.2  feet  from  grade  represents  good  construction  and 
that  the  combination  of  construction  errors  and  settlement  fre- 
quently exceeds  this  amount  even  on  well-built  flumes,  particu- 
larly if  the  trestle  is  high.  If  settling  can  be  checked  the  stringers 
can  be  raised  on  the  caps  or  the  sides  of  the  flume  heightened. 
Sufficient  freeboard  should  be  allowed  in  the  original  plans  to 
allow  for  minor  settlement.  A  small  flow  should  be  run  through 
the  flume  for  a  sufficient  length  of  time  in  the  spring  to  swell  the 
wood  and  reduce  leakage  before  the  full  load  is  carried. 

Single  spans  may  settle  due  to  erosion  around  the  footings 
adjacent  to  stream  channels.  It  is  preferable  to  carry  the  flume 
on  long  trussed  spans  over  such  points.  If  such  erosion  occurs 
means  of  protection  adapted  to  local  conditions  must  be  used. 

The  maintenance  of  the  trestles  of  steel  flumes  is  similar  to 
that  for  wood  flumes.  -.The  smaller  amount  of  leakage  with  steel 
flumes  should  reduce  the  liability  of  softening  of  the  footings 
and  consequent  settlement.  Some  adjustment  of  the  bands 
on  steel  flumes  will  usually  be  necessary  each  season  to  prevent 
leakage.  Steel  flumes  may  also  give  trouble  if  sufficient  provision 
for  expansion  and  contraction  has  not  been  made.  Concrete 
flumes  should  require  little  maintenance;  their  greater  weight, 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       71 

however,  makes  the  use  of  greater  care  in  the  footings  necessary. 
They  are  special  structures  which  have  not  been  in  use  to  a 
sufficient  extent  to  furnish  direct  experience. 

The  maintenance  of  inlets  and  outlets  of  flumes  is  similar  to 
that  for  checks  and  drops.  Cutting  under  or  around  the  cutoff 
and  wings  must  be  prevented. 

MAINTENANCE  OF  CONCRETE-LINED  CANALS 

One  of  the  advantages  of  lining,  particularly  of  concrete  lining, 
is  the  reduction  in  maintenance  cost.  This  may  be  due  to  the 
prevention  of  aquatic  growths,  and  of  erosion  or  silting,  or  to 
the  lessened  liability  of  canal  breaks  due  to  burrowing  animals 
and  the  softening  of  banks  due  to  seepage.  Ordinarily  the  main- 
tenance cost  for  such  lining  is  relatively  low.  Injury  more  often 
results  from  the  outside  than  from  the  inside  of  the  canal,  such 
as  that  due  to  the  failure  of  the  earth  backing.  In  one  instance 
on  the  Umatilla  project,  cracks  in  the  lining  permitted  sufficient 
leakage  so  that  erosion  behind  the  lining  resulted  in  a  break. 
With  relatively  deep  canals  the  pressure  of  the  earth  during  the 
non-operating  season  may  be  sufficient  to  force  the  lining  out  of 
position.  This  may  be  due  to  frost  action  or  to  the  pressure 
of  saturated  earth  alone.  This  latter  condition  has  been  en- 
countered to  some  extent  on  the  South  San  Joaquin  system  in 
California.  In  some  cases  the  canals  were  filled  with  water  held 
by  checks,  the  pressure  of  the  water  resisting  that  of  the  earth ;  in 
others,  the  lining  was  broken  into  blocks  and  relaid  as  riprap, 
the  drainage  through  which  prevented  the  accumulation  of 
pressure. 

The  use  of  concrete  even  with  relatively  high  velocities  will 
not  prevent  the  growth  of  aquatic  vegetation  in  many  cases. 
In  Southern  California  a  moss-like  growth  of  considerable  length 
may  attach  itself  to  the  lining,  particularly  on  the  sides.  This  is 
generally  removed  with  an  implement  similar  to  a  hoe  with  the 
blade  in  line  with  the  handle,  the  growth  being  scraped  off  and 
removed  as  it  is  carried  down  the  canal.  As  many  as  three  or 
four  cleanings  per  season  may  be  required.  Where  such  vegeta- 
tion occurs  in  concrete  lining  the  average  value  of  n  in  Kutter's 
formula  has  been  found  to  be  about  0.016  whether  the  concrete 
itself  is  very  smooth  or  has  only  an  ordinary  finish  (Plate  III, 
Fig.  C).  On  the  Tieton  main  canal  in  Washington  where  the 


72  IRRIGATION  SYSTEMS 

velocity  approaches  9  feet  per  second  a  form  of  growth  attaches 
itself  to  the  concrete  particularly  near  the  water  surface  although 
the  concrete  is  quite  smooth.  This  growth  can  be  removed  by 
shutting  water  out  for  2  or  3  days,  when  its  hold  becomes 
weakened  so  that  on  turning  water  in  again  practically  all  of 
the  growth  will  be  washed  off.  Tests  on  this  canal  have  shown 
a  quite  regular  seasonal  variation  of  the  value  of  n  in  Kutter's 
formula  due  to  this  growth.  In  the  spring,  when  clean,  the 
value  of  n  is  about  0.012;  during  the  season  it  rises  to  a  value 
of  0.013.  On  other  systems  the  pond-weed  or  common  "moss" 
grows  to  sufficient  length  so  that  sawing  or  other  means  used  in 
earth  canals  are  required. 

BRIDGES 

In  all  States,  when  a  canal  is  built  across  a  public  road  the 
canal  owner  is  required  by  law  to  construct  a  bridge  over  the  canal. 
In  Colorado,  Idaho,  Montana,  New  Mexico  and  Wyoming  the 
county  will  maintain  such  bridges,  usually  after  they  have 
been  built  and  maintained  for  1  year  by  the  canal  owner.  In 
Arizona,  Oregon,  and  Nevada  the  canal  company  is  required  to 
maintain  as  well  as  to  construct  the  bridges;  in  the  other  States 
the  taking  over  of  the  maintenance  is  usually  optional  with 
the  county  officials,  specific  statements  not  being  made  in  this 
regard  in  the  statutes  of  some  States.  The  county  officials  are 
generally  given  authority  to  require  bridges  which  meet  their 
approval,  particularly  where  the  county  is  to  maintain  them. 
Such  requirements  are  usually  quite  general,  however.  Failure 
on  the  part  of  the  canal  owner  to  construct  or  to  repair  a  bridge 
when  ordered  to  do  so  by  the  county  renders  the  owner  liable 
to  fine  or  even  imprisonment  in  some  States;  more  usually, 
however,  if  the  work  is  not  done  within  from  3  to  10  days  after 
notice  is  given  the  county  can  do  the  work  and  charge  the  costs 
to  the  canal  owner. 

The  following  statute  of  Wyoming  is  typical  (Paragraph  2567) . 

"Owner  of  Canal  Must  Maintain  Bridge  at  Road  Crossing. — Any 
person,  company,  corporation  or  association  of  persons,  operating  or 
maintaining  in  whole  or  in  part,  either  as  owners,  agent,  occupant  or 
appropriator  any  ditch,  canal  or  water  course,  not  being  a  natural 
stream,  for  irrigation  or  any  other,  and  different  purpose,  shall  put  in, 
construct,  maintain  and  keep  in  repair  at  his,  her,  its  or  their  expense, 
for  one  year,  where  the  same  crosses  any  public  highway  or  publicly 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       73 

traveled  road,  a  good  substantial  bridge,  not  less  than  fourteen  feet  in 
width,  over  such  ditch,  canal  or  water  course  where  it  crosses  such 
road.  Any  violation  of  the  provisions  of  this  section  shall  be  a  mis- 
demeanor, and  upon  conviction  thereof,  the  person  so  offending  shall 
pay  a  fine  in  any  sum  not  exceeding  one  hundred  dollars  for  each  day 
such  ditch,  canal  or  water  course  shall  be  unbridged,  insufficiently 
bridged,  or  permitted  to  remain  out  of  repair;  Provided,  that  after  the 
expiration  of  one  year,  from  the  construction  of  said  bridge,  the  road 
supervisor  of  the  road  district  in  which  said  bridge  is  located,  shall  upon 
being  notified  by  the  owner  or  owners  of  the  ditch,  canal  or  water  course 
over  which  such  bridge  is  constructed,  at  once  inspect  said  bridge,  and 
if  found  in  a  good  and  lawful  condition,  shall  accept  the  same  for  the 
county  in  which  it  is  located,  and  said  bridge  shall  thereafter  be  main- 
tained by  the  said  county"  (L.  1895,  ch.  69,  Paragraph  55;  R.  S.  1899, 
Paragraph  1959;  L.  1901,  ch.  21). 

The  above  discussion  applies  where  the  road  is  in  use  before 
the  construction  of  the  canal.  When  a  new  public  road  is 
opened  across  a  canal,  the  public  is  required  to  build  the  bridge. 
In  the  City  of  Madera  vs.  Madera  Canal  &  Irrigation  Co.  (115 
Pac.  936)  it  was  held  that  the  canal  owner  must  prepare  the  right 
of  way  so  as  not  to  obstruct  the  road  but  this  does  not  include 
the  bridge  which  is  a  part  of  the  road.  The  canal  owner  must 
prepare  the  banks  of  the  canal  so  that  they  will  not  interfere 
with  access  to  the  bridge.  California  statutes  provide  that  no 
damages  shall  be  given  for  a  right  of  way  for  a  road  across  a 
canal. 

Bridges  across  canals  on  private  roads  or  to  reach  parts  of  a 
farm  intersected  by  the  canal  may  be  built  by  either  the  canal 
company  or  the  land  owner.  Such  bridges  are  frequently  made 
a  part  of  the  right-of-way  agreement  when  the  canal  is  built 
through  lands  in  private  ownership,  the  canal  company  more 
often  building  such  bridges  as  a  part  of  the  right-of-way  con- 
sideration. If  the  canal  company  also  controls  the  ownership 
of  the  land  at  the  time  of  construction  as  in  colonization  or  Carey 
Act  systems,  it  may  be  considered  to  be  better  policy  to  construct 
such  bridges  and  include  their  cost  in  the  price  of  the  land. 
Where  additional  bridges  are  desired  after  construction,  the  cost 
is  more  usually  paid  by  the  land  owner  and  the  bridges  either 
built  by  or  the  character  of  construction  approved  by  the  canal 
owner.  Such  additional  bridges  will  be  needed  as  land  holdings 
are  subdivided.  Larger  bridges  such  as  those  over  main  canals 
and  large  laterals  are  better  built  by  the  canal  company;  small 


74  IRRIGATION  SYSTEMS 

ones,  such  as  single-span  stringer  bridges,  may  be  built  by  either 
the  canal  company  or  land  owner.  Such  bridges  do  not  usually 
need  to  be  of  as  heavy  construction  as  bridges  on  public  roads. 

The  kinds  of  bridges  for  public  roads  may  be  controlled  by 
the  legal  requirements.  In  Oregon,  Colorado,  and  New  Mexico 
and  Wyoming,  such  bridges  must  be  at  least  14  feet  wide;  in 
Washington  and  Idaho,  16  feet  wide.  In  Nevada  they  must  be 
built  according  to  the  standard  plans  and  specifications  of  the 
county  commissioners.  The  Idaho  statute  further  requires  easy 
grades  on  and  off  the  bridge,  floor  not  less  than  3  inches  thick 
on  stringers  not  less  than  6  inches  square  nor  more  than  3  feet 
apart  unless  the  canal  is  small  enough  to  be  carried  in  a  culvert. 
When  a  bridge  is  built,  the  canal  owner  reports  to  the  road 
supervisor  and  on  acceptance  of  the  bridge  it  becomes  county 
property. 

An  18-ton  tractor  is  as  heavy  a  load  as  is  to  be  expected  on 
county  bridges.  Several  States  have  laws  requiring  those 
crossing  bridges  with  tractors  to  lay  heavy  planking  or  use  other 
methods  to  strengthen  the  bridge.  The  heaviest  wagon  loads  are 
those  used  in  hauling  sugar  beets  and  may  amount  to  7  or  8  tons. 

Wood-stringer  bridges  can  be  used  up  to  16-  or  even  20-foot 
spans.  With  16-foot  roadway  these  can  usually  be  built  for 
$5  or  $6  per  foot  of  span.  Such  bridges  with  multiple  spans  are 
frequently  used  in  larger  canals,  being  cheaper  than  trusses. 
Where  drift  is  liable  to  catch  on  the  piers  or  where  erosion  around 
the  pier  footings  may  take  place,  such  bridges  may  not  be  de- 
sirable. Permanent  pier  footings  of  concrete  projecting  about 
the  canal  grade  increase  the  life  of  the  posts  and  reduce  main- 
tenance costs.  Maintenance  consists  mainly  in  replacing  the 
flooring  due  to  its  wear  under  traffic.  Where  the  canal  section 
is  restricted  by  the  end  walls,  some  cutting  of  adjacent  canal 
banks  may  occur.  It  is  usually  cheaper  in  the  end  to  make  the 
span  equal  to  the  water-surface  width  at  full-supply  level. 
Clearance  above  full-supply  level  should  be  sufficient  to  prevent 
drift  catching  on  the  stringers.  Substantial  railings  on  the 
bridge  and  approaches  are  needed  on  highway  bridges.  Farm 
bridges  can  be  made  narrower  and  the  railings  omitted.  A  wheel 
guard  should  be  used,  however. 

Fording  of  canals  should  not  be  permitted  unless  a  wide  shallow 
section  is  provided  and  crossing  should  be  restricted  to  bridges. 
Fording  by  cattle  breaks  down  the  canal  slopes. 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       75 

TELEPHONES 

Telephone  lines  are  essential  in  the  operation  of  any  large 
irrigation  system  and  their  ownership  and  control  by  the  canal 
system  is  preferable.  On  the  canals,  such  telephone  systems 
should  connect  each  ditch  rider's  house  with  the  main  office 
so  that  daily  reports  can  be  made  where  these  are  used  or  that 
orders  for  the  following  day  may  be  given.  There  should  also 
be  connections  by  which  the  riders  can  reach  headquarters  quickly 
in  case  of  trouble  on  the  canals.  This  can  best  be  accomplished 
by  having  a  telephone  line  along  the  main  canal  with  telephones 
at  intervals  or  by  having  the  rider  carry  a  portable  instrument. 
The  former  method  is  more  usual.  On  laterals  which  are  located 
in  well-settled  districts  supplied  with  local  telephone  service, 
separate  canal  lines  are  not  necessary.  However,  in  order  to 
avoid  the  delays  and  uncertainties  of  service  on  farm  party  lines, 
it  is  an  advantage  to  have  a. separate  system  to  each  ditch  rider's 
headquarters.  Direct  telephone  service  to  the  headworks  or 
wasteways  is  needed  so  that  water  can  be  shut  out  promptly 
in  case  of  breaks  in  the  system. 

In  some  cases  service  arrangements  are  made  with  local  tele- 
phone companies.  This  is  not  generally  desirable  for  the  main 
lines  as  the  cost  of  building  connections  outside  the  settled  areas 
may  be  nearly  as  great  as  that  of  constructing  an  independent 
system.  During  the  first  years  of  operation  the  settlement  of 
the  lands  may  not  be  sufficient  to  warrant  the  construction  of 
such  local  systems  and  independent  canal  lines  may  be  neces- 
sary. In  such  cases  there  is  usually  a  demand  from  settlers  to 
be  allowed  to  use  the  company  lines.  It  is  not  usual  to  permit 
such  use  except  in  cases  of  emergency.  After  the  lands  have 
become  settled  and  developed,  local  service  within  the  irrigated 
area  may  be  used. 

Such  telephone  lines  are  of  two  kinds:  metallic  circuits,  in 
which  two  wires  are  used;  and  grounded  circuits,  in  which  one 
wire  grounded  to  the  earth  is  used.  The  grounded  line  is  some- 
what cheaper  but  the  service  is  generally  not  as  satisfactory. 
Only  a  few  telephones,  preferably  not  over  eight  or  ten,  can  be 
used  on  grounded  lines  and  if  the  line  is  long  it  may  be  difficult 
to  get  distinct  transmission  unless  the  grounds  are  very  carefully 
made.  Return  circuits  can  carry  more  connected  telephones 
and  usually  give  clearer  transmission.  Telephone  sets  arranged 


76 


IRRIGATION  SYSTEMS 


so  as  to  be  switched  off  the  line  when  not  in  use  are  preferable. 
About  twice  as  many  of  such  instruments  can  be  carried  on  a 
single  circuit  as  compared  with  call  telephones. 

The  average  amount  of  material  required  per  mile  of  telephone 
line  is  given  in  Table  VI. 

TABLE  VI. — MATERIALS  REQUIRED  PER  MILE  OF  TELEPHONE  LINE 


Amount 

required 

Ground 
circuit 

Metallic 
circuit 

25-foot  poles  (6  inches  top  diameter)  

33 

33 

40-foot  poles  (6  inches  top  diameter)  at  road  crossings.. 
No.  12  B.W.G.,  B.B.  galvanized-iron  wire  nails,  pounds 

2 
165 

2 

330 

Glass  insulators  

40 

75 

12-inch  wood  brackets 

40 

75 

60d  galvanized-steel  wire  nails,  pounds  

8 

15 

^-inch  X  6-foot  galvanized-iron  anchor  rods 

5 

5 

*^}-inch  7-strand  galvanized  guy  wire  feet 

100 

100 

The  cost  of  such  telephone  lines  varies  with  the  price  of  mate- 
rial, character  of  excavation  for  the  poles  and  other  factors. 
Ground  circuits  can  usually  be  built  for  from  $80  to  $150  per 
mile;  metallic  circuits  cost  $15  to  $25  more  per  mile. 

The  15th  Annual  Report  of  the  U.  S.  Reclamation  Service 
gives  the  average  cost  of  2,376  miles  of  telephone  line  as  about 
$185  per  mile.  An  average  of  one  telephone  to  each  2.4  miles  of 
line  was  in  use.  For  the  area  which  the  Service  was  prepared  to 
irrigate  in  1916,  on  all  projects,  there  was  an  average  of  1  mile  of 
telephone  lines  for  each  640  acres,  usually  varying  from  300  to 
1,200  acres  on  different  projects.  The  cost  of  telephone  lines  has 
been  about  0.4  per  cent,  of  the  total  expenditures,  or  an  average 
of  26  cents  per  acre  for  the  area  irrigable  in  1916.  The  telephone 
lines  of  these  projects  are  probably  more  extensive  than  those  on 
many  other  systems  so  that  these  figures  should  represent  as  high 
a  total  cost  as  is  to  be  expected. 

The  telephone  system  on  the  Imperial  Valley  Water  Co.  No.  1 
consisted  of  48  miles  of  line,  31  telephones  and  one  switchboard 
in  1915,  having  a  value  of  $9,940  or  $207  per  mile  of  line. 

Ditch  riders  can  patrol  the  parts  of  the  telephone  system 
which  parallel  their  beats.  This  may  make  it  desirable  to  carry 
such  lines  along  canals  although  the  length  might  be  reduced  by 


MAINTENANCE  OF  IRRIGATION  SYSTEMS       77 

more  direct  lines.  It  will  also  usually  be  necessary  to  have  avail- 
able a  troubleman  for  repairs  which  cannot  be  made  by  the  ditch 
riders.  Such  a  troubleman  may  be  a  member  of  maintenance 
crews  and  give  only  part  time  to  telephone  repairs. 

Where  lines  are  carried  through  timber,  trees  may  be  used 
for  poles.  Grounded  lines  are  preferable  due  to  the  danger  of 
short-circuiting  by  falling  branches.  More  slack  should  also  be 
given.  The  standard  construction  of  the  U.  S.  Forest  Service  is 
a  grounded  line  of  No.  9  B.W.G.  Best  Wire. 

On  large  systems  more  than  one  shift  of  telephone  operators 
may  be  used.  It  is  more  usual,  however,  to  arrange  for  night  calls 
to  be  received  by  some  employee  not  regularly  on  duty.  This 
may  be  done  by  connecting  the  superintendent's  residence  with 
the  system  so  that  he  may  be  called  directly  or  by  having  some 
employee  quartered  in  the  building  in  which  the  switchboard  is 
located.  During  the  day  special  operators  may  be  used  if  the 
number  of  calls  warrant  it ;  more  usually  such  employees  can  also 
do  certain  other  routine  or  clerical  work  as  well.  The  cost  of  oper- 
ation is  practically  the  salary  paid  to  such  operators.  These  are 
usually  necessary  only  during  the  operation  season.  The  cost 
of  maintenance  may  be  as  high  as  $30  per  mile  per  year  although 
little  direct  data  regarding  such  costs  are  available. 

REFERENCES  FOR  CHAPTER  II 

CORY,  H.  T. — Irrigation  and  River  Control  in  the  Colorado  River  Delta, 
1913,  p.  1429,  Vol.  LXXVI,  Transactions  of  the  American  Society  of 
Civil  Engineers. 

HARDING,  S.  T. — Comparison  of  Wood  and  Concrete  for  Use  in  Irrigation 
Structures,  Engineering  and  Contracting,  April  12,  1916. 

ARMSTRONG,  W.  B. — Maintenance  and  Construction  of  Metal  Flumes,  1916, 
Third  Proceedings,  Washington  Irrigation  Institute,  No.  Yakima,  Wash. 

TIFFANY,  R.  K. — Experience  with  Wood  Stave  Pipe  in  Irrigation,  Engineer- 
ing News,  Feb.  6,  1913. 

NOBLE,  T.  A. — Wood  Pipe:  Its  Uses  and  Limitations,  1916,  Third  Proceed- 
ings Washington  Irrigation  Institute,  No.  Yakima,  Wash. 

SWICKARD,  ANDREW. — Durability  of  Wood  Stave  Pipe,  Engineering  and 
Contracting,  Dec.  2,  1914. 

HENNY,  D.  C. — Life  of  Wood  Pipe,  Reclamation  Record,  August,  1915. 

WIG,  R.  J.  and  others. — Investigation  of  the  Durability  of  Cement 
Drain  Tile  in  Alkali  Soils,  1915,  Technologic  Paper  44,  U.  S.  Bureau 
of  Standards. 

BANKS,  F.  A. — Relative  Value  of  Permanent  and  Temporary  Structures  for 
Lateral  Systems,  1913,  Second  Conference  of  Operating  Engineers, 
Boise,  Idaho. 


78  IRRIGATION  SYSTEMS 

BURKY,  C.  R. — Maintenance  Problems,  1914,  Third  Conference  of  Operat- 
ing Engineers,  Boise,  Idaho. 

WALTER,  R.  F. — Condition  of  Pure  Iron  Pipe  Siphon  in  Alkali  Soil,  Engi- 
neering Record,  Dec.  5,  1914. 

METCALF,  L. — Protection  of  Riveted  Steel  Pipe,  Engineering  and  Contract- 
ing, Dec.  30,  1914. 

DAVIS  AND  HENNY. — Dams,  Transactions  of  the  International  Engineering 
Congress,  1915,  Waterways  and  Irrigation,  San  Francisco,  Cal. 

LYTEL,  J.  L. — Waterproofing  Concrete  Surfaces,  Reclamation  Record, 
April,  1915. 

Telephone  Construction  and  Maintenance  on  National  Forests,  1915, 
Miscellaneous  (0-3)  Forest  Service,  U.  S.  Department  of  Agriculture. 

STOCKTON,  R.  S. — Management  of  Irrigation  Systems,  Engineering  and 
Contracting,  Jan.  28,  1914. 

PYLE,  F.  D. — Care  and  Attention  Necessary  for  Maintenance  of  Metal 
Flumes,  Reclamation  Record,  November,  1916. 


CHAPTER  III 

ORGANIZATION  FOR  OPERATION  AND  MAINTENANCE 
GENERAL  ORGANIZATION 

The  duties  and  requirements  of  an  organization  for  the  opera- 
tion and  maintenance  of  an  irrigation  system  differ  from  those  for 
its  original  construction  or  extensive  betterment.  During  the 
first  years  of  operation  there  may  be  a  large  amount  of  construc- 
tion remaining  to  be  done,  so  that  it  may  be  necessary  to  main- 
tain the  two  forms  of  organization. 

The  organization  of  different  systems  varies  widely  both  in  the 
character  of  the  duties  that  may  be  handled  and  the  extent  to 
which  they  may  be  carried  out.  There  are  several  factors  which 
affect  the  form  of  organization  which  may  be  used,  among 
which  are:  (1)  size  of  system,  (2)  character  of  the  company, 
(3)  the  method  of  delivery,  (4)  value  of  water,  and  (5)  average 
size  of  farm. 

The  size  of  the  system  or  area  irrigated  is  the  most  important 
factor  in  determining  the  extent  of  the  organization.  On  some 
of  the  smaller  or  simpler  systems  the  entire  office  work  may  be 
handled  by  a  secretary  on  part  time.  It  is  only  on  the  larger 
and  more  complex  systems  that  a  complete  organization  is 
needed  or  that  its  cost  can  be  afforded.  On  large  canals,  some 
definite  system  both  for  the  delivery  of  water  and  for  the  records 
is  required  if  satisfactory  results  are  to  be  secured.  It  is  probable 
that  the  average  cost  per  acre  for  the  organization  is  higher  on 
many  large  systems  than  on  the  smaller  ones,  the  greater  amount 
of  detail  handled  on  such  large  systems  more 'than  balancing  the 
lower  cost  per  unit  accomplished  which  can  be  secured  where 
the  amount  to  be  done  is  larger.  This  is  due  also  to  the  fact  that 
canals  covering  large  areas  are  more  complicated  as  the  more 
easily  covered  lower  .lands  are  usually  served  by  the  smaller 
canals.  With  large  systems  the  prospective  damages  due  to 
possible  breaks  are  greater  and  a  closer  control  of  the  water  is 
essential.  With  large  areas  more  book  records  are  required,  as 

79 


80  IRRIGATION  SYSTEMS 

there  is  less  of  the  individual  contact  between  the  irrigators  and 
the  operation  officials  other  than  the  ditch  riders.  On  small 
systems  a  secretary  and  the  ditch  riders  may  comprise  the  operat- 
ing force.  As  the  size  increases  and  more  ditch  riders  are  needed, 
the  secretary  may  also  be  the  superintendent  or  a  separate 
superintendent  may  be  employed  to  direct  the  ditch  riders  and 
also  to  handle  maintenance  and  engineering  work  directly.  With 
further  increases  in  size  the  organization  becomes  more  complex 
until  with  the  very  large  systems  the  duties  under  each  division 
of  the  work  are  sufficient  in  amount  to  require  the  continuous 
time  of  at  least  one  man. 

The  character  of  the  controlling  company  very  materially 
affects  the  operation  organization.  With  systems  controlled  by 
the  land  owners,  such  as  cooperative  companies  or  irrigation  dis- 
tricts, the  more  simple  and  less  expensive  organizations  are 
general.  This  result  is  secured  partly  by  doing  without  some  of 
the  service  which  may  be  given  by  the  more  highly  developed 
organizations  such  as  hydrographic  and  similar  work  and  also 
partly  by  using  a  somewhat  lower  average  scale  of  pay.  The 
systems  of  the  U.  S.  Reclamation  Service  generally  have  the  most 
complete  and  detailed  organizations.  This  is  partly  due  to  the 
necessity  of  following  governmental  requirements  as  to  accounts 
and  records  and  partly  to  the  use  of  a  more  detailed  control  of 
delivery  and  use  of  water  than  are  usual  on  other  systems.  Such 
government  projects  are  also  subject  to  the  inherent  disadvantage 
of  all  government  work  where  the  lack  of  direct  responsibility 
to  those  actually  supplying  the  funds  from  their  own  resources 
makes  the  incentive  for  economy  less  direct.  This  is  being  partly 
overcome  in  some  cases  by  giving  the  settlers  under  each  project 
a  larger  share  in  the  selection  of  the  policies  for  the  system. 
With  Carey  Act  projects,  a  wide  variety  of  conditions  are  found. 
Some  have  quite  complete  operation  organizations,  others  oper- 
ate as  cheaply  as  possible  until  the  system  can  be  turned  over  to 
the  settlers.  As  it  has  become  recognized  that  the  time  until 
such  systems  can  be  turned  over  to  the  settlers  is  longer  than 
many  Carey  Act  projects  first  anticipated,  the  tendency  is  toward 
more  complete  operating  organizations  and  better  maintenance. 
The  commercial  or  public  utility  irrigation  companies  generally 
use  organizations  of  similar  detail  to  those  of  other  similar  corpo- 
rations, the  result  being  that  usually  less  detail  control  is  exer- 
cised than  on  the  government  systems.  In  several  States  such 


OPERATION  AND  MAINTENANCE  81 

utility  companies  are  subject  to  public  control  in  regard  to  the 
service  given  which  in  turn  affects  or  controls  the  organization 
which  it  is  necessary  to  use. 

The  method  of  delivery,  which  is  itself  influenced  by  the  value 
of  water,  controls  some  portions  of  the  organization.  Where 
quantity  rates  are  used,  more  detail  individual  records  are  re- 
quired, which  make  necessary  larger  organizations,  particularly 
in  the  hydrographic  work.  Where  the  water  supply  is  ample  it 
is  cheaper  to  have  some  excess  canal  capacity  and  looser  opera- 
tion methods  than  to  closely  control  the  use  of  a  smaller  supply 
for  the  same  area.  Where  the  cost  of  the  water  itself  is  relatively 
high,  relatively  expensive  organizations  for  securing  more  eco- 
nomical use  are  warranted.  The  average  size  of  farm  affects 
the  organization.  For  small  farms  more  deliveries  and  greater 
detail  of  records  are  required;  for  large  farms  using  a  continuous 
flow  little  detailed  attention  in  operation  is  required.  Similarly, 
delivery  to  laterals  only  instead  of  to  individuals  very  materially 
reduces  the  extent  and  complexity  of  the  main-canal  organization. 

The  value  of  good  service  is  becoming  more  generally  recog- 
nized and  the  tendency  is  toward  a  more  complete  control  of  the 
systems  by  a  more  detailed  organization  in  order  that  such  better 
service  can  be  consistently  given. 

Organization  Divisions. — Three  general  divisions  of  the  organi- 
zation can  be  made,  the  duties  of  which  are  fairly  distinct  although 
the  actual  personnel  may  overlap,  particularly  on  the  smaller 
systems.  These  are:  (1)  the  operation  proper  or  delivery  of 
water  division,  (2)  the  engineering  division,  and  (3)  the  clerical 
division.  The*  following  outline  chart  shows  the  organization 
and  duties  that  come  within  the  different  divisions.  A  some- 
what similar  chart  has  been  prepared  by  G.  H.  Bliss  of  the  Boise 
project  of  the  Reclamation  Service,  references  to  which  are  given 
at  the  end  of  the  chapter.  Only  large  systems  would  use  such  an 
organization  in  its  entirety,  it  covers  practically  all  duties  that 
would  be  performed  on  any  system  and  as  such  forms  a  good  basis 
of  discussion.  On  the  larger  number  of  systems  some  of  the  duties 
would  be  omitted  or  combined  with  others. 

Organization  Chart 
GENERAL  SUPERVISION. 

Board  of  directors  or  equivalent.     Determines  the  general  policies 
and  expenditures  of  the  system. 


82  IRRIGATION  SY STEMS 

DIRECT  SUPERVISION. 

Manager,  directly  responsible  for  the  expenditures  and  the  carry- 
ing out  the  policies  of  the  directors;  heads  of  divisions  directly 
under  his  supervision  on  large  systems ;  on  smaller  systems  manager 
may  also  act  as  the  head  of  the  divisions.     Assistant  manager  may 
also  be  used  in  some  cases.    Under  the  manager  come  the  following 
more  or  less  distinct  divisions: 
Operation  division. 
Engineering  division. 
Clerical  division. 

In  addition  there  may  be  legal  department  either  permanently 
maintained  or  retained  or  employed  only  as  needed. 
OPERATION  DIVISION. 

Usually  in  charge  of  the  superintendent  or  water  master,  handles 
the  securing  of  water  and  its  delivery  and  the  maintenance  of  the 
system  during  the  delivery  season.  Also,  usually  handles  main- 
tenance work  during  non-delivery  season  except  the  larger  con- 
struction work  which  may  be  handled  by  the  engineering  division. 
Superintendent  controls  division  of  water  to  the  different  clitch- 
rider  beats,  handles  complaints  not  settled  by  ditch  riders,  super- 
vises maintenance  crews  and  generally  directs  the  operation.  On 
large  systems,  two  or  more  superintendents  reporting  to  the 
manager  may  be  used,  each  having  charge  of  a  particular  division 
or  unit.  Under  the  operation  department  are  the: 

Ditch  riders,  or  equivalent  employees,  who  are  assigned  to 
definite  beats,  on  which  they  make  deliveries  of  water,  patrol 
their  assigned  ditches,  make  minor  repairs  and  notify  super- 
intendent of  those  requiring  the  maintenance  crew. 
Gate  tenders  at  reservoirs  or  headgates. 

Maintenance   foremen,   who   handle   small   crews  who  make 
repairs  as  needed  on  any  part  of  the  system,  and  install  new 
delivery    gates    or    minor    structures    as    required.     Handles 
vegetation  in  canals  and  on  canal  banks  when  too  large  in 
amount  to  be  controlled  by  the  ditch  riders. 
Telephone  operators  and  linemen,  who  operate  and  maintain 
telephone   service   when   separate   systems    are   owned    and 
operated  by  the  canal  company;  linemen  may  be  combined 
with  the  maintenance  crew.     It  is  desirable  to  have  24-hour 
connection  with  superintendent  on  large  systems. 
Superintendents'  clerk,  who  handles  routine  matters  such  as 
records  of  complaints,  timekeeping,  etc.    Sometimes  combined 
with  the  clerical  department. 
ENGINEERING  DIVISION. 

Usually  in  charge  of  the  engineer  or  assistant  engineer  who  may  also 
be  the  superintendent;  handles  all  strictly  engineering  matters, 


OPERATION  AND  MAINTENANCE  83 

such  as  the  construction  of  extensions,  larger  betterments  or  other 
work  important  enough  to  be  distinguished  from  ordinary  main- 
tenance. Under  the  engineering  department  are : 

Instrumentmen,  who  handle  field  surveys,  stake  out  construction 
work,  etc. 

Inspectors,  who  inspect  construction,  usually  combined  with 
instrumentmen. 

Draftsmen,  who  handle  office  work  for  engineer.     This  may 
also  be  handled  by  instrumentmen. 

Hydrographer,   who  handles  ratings  of  canals  and  delivery 
devices,  compiles  hydrographic  records,  makes  seepage  measure- 
ments, ground-water  studies  where  such  are  needed,  compiles 
water-delivery  records  in  shape  to  be  posted  by  the  clerical 
division  where  water  is  sold  on  a  quantity  basis. 
General  foreman  or  construction  superintendent,  who  handles 
force-account    construction    work    which    comes    under    the 
engineering  department. 
CLERICAL  DIVISION. 

In  charge  of  secretary  or  chief  clerk,  who  handles  clerical  and  fiscal 
matters.  The  duties  handled  include: 

Collections  of  assessments  and  charges. 
General  accounting  system. 

Purchasing  of  supplies  and  materials  ordered  by  other  de- 
partments. 
Messes  and  corrals. 
Equipment  inventories. 
Storehouse  supervision. 
Correspondence. 

General  Supervision. — General  supervision  should  be  exercised 
by  those  responsible  for  the  policies  of  the  system.  For  enter- 
prises controlled  by  the  land  owners  this  will  be  the  board  of 
directors  elected  by  the  owners.  The  manager  should  be  given 
full  control  in  carrying  out  the  actual  operation  and  maintenance. 
It  is  not  desirable  to  have  the  board  of  directors  act  directly 
as  manager;  there  should  be  some  single  individual  with  full 
authority  and  responsibility  who  is  judged  by  the  results  and  left 
free,  except  in  matters  of  general  policy,  to  secure  the  results  by  his 
own  methods.  The  duties  of  direct  management  of  large  systems 
require  an  experience  not  usually  possessed  by  the  elected  directors. 

Direct  Supervision. — The  duties  of  a  manager  require  both 
executive  ability  and  engineering  and  agricultural  experience. 
Executive  training  has  been  more  readily  secured  in  the  past  in 
engineering  than  in  agricultural  lines  so  that  the  majority  of 


84  IRRIGATION  SYSTEMS 

present  managers  have  been  trained  in  engineering.  Frequently 
engineers  connected  with  the  construction  of  a  system  will  remain 
with  it  during  operation.  Strictly,  engineering  training  may, 
however  be  a  disadvantage,  unless  there  is  combined  with  it  some 
general  agricultural  knowledge  and  an  understanding  of  agricul- 
tural conditions  and  people.  Knowledge  of  the  use  of 
water  is  as  essential  as  knowledge  of  its  development  and  con- 
veyance. The  best  training  is  in  actual  operation,  such  as  can  be 
obtained  by  working  up  through  the  operation  department  or 
through  the  hydrographic  work  of  the  engineering  department. 

The  positions  of  irrigation  managers  paying  sufficient  salaries 
to  be  permanently  attractive  to  properly  qualified  men  have 
been  largely  a  development  of  the  past  15  years.  This  is  coinci- 
dent with  the  construction  of  the  greater  number  of  large  systems 
whose  size  is  sufficient  to  enable  them  to  pay  such  salaries.  Such 
positions  tend  to  be  more  permanent  and  remunerative  on 
systems  controlled  by  corporations.  The  larger  cooperative 
systems  in  many  cases  do  not  appreciate  the  economies  which  a 
good  manager  may  effect.  With  such  cooperative  companies 
the  salary  is  often  on  a  lower  scale  and  where  the  members  of  the 
board  of  directors  are  frequently  changed,  the  tenure  of  the 
position  may  be  less  certain. 

Much  has  been  written  regarding  the  difficulties  of  such  posi- 
tions and  the  necessary  qualifications  of  an  irrigation  manager. 
The  general  qualifications  needed  are  similar  to  those  required  by 
the  manager  of  any  service  which  delivers  to  a  large  number  of 
consumers  any  of  their  necessities.  These  include  a  knowledge 
of  how  to  be  firm  and  insistent  when  necessary,  but  a  better 
knowledge  of  how  to  avoid  the  need  of  such  insistence  and  a 
uniformity  and  fairness  in  dealing  with  all  classes,  both  successful 
and  unsuccessful. 

The  assistant  manager  as  a  distinct  position  is  not  usual.  The 
head  of  one  of  the  departments,  generally  the  operation  division, 
may  become  acting  manager  in  the  manager's  absence.  When  a 
system  is  so  large  that  assistant  managers  are  needed,  it  may  be 
preferable  to  divide  the  system  into  units  in  each  of  which  the 
organization  is  more  or  less  distinct. 

OPERATION  DIVISION 

•  The  main  purpose  of  an  irrigation  system  is  to  deliver 
water  at  the  times  and  in  the  quantities  needed  to  produce  the 


OPERATION  AND  MAINTENANCE  85 

best  results  from  its  use.  This  is  the  duty  of  the  operation  de- 
partment and  it  is,  therefore,  the  most  important  of  the  three  di- 
visions outlined.  It  is  the  one  that  comes  into  the  most  direct 
and  closest  contact  with  the  irrigators  and  the  one  by  which  the 
land  owners  often  judge  the  whole  organization.  As  previously 
stated,  the  personnel  may  overlap  and  be  interchangeable  with  the 
other  divisions;  the  duties  of  the  operation  department  are  rela- 
tively definite,  however. 

The  operation  department  is  usually  in  charge  of  a  superin- 
tendent or  water  master  who  is  the  authority  next  above  the  ditch 
riders.  A  capable  superintendent  can  often  secure  results  which 
no  other  member  of  the  organization  could  accomplish,  due  to 
having  sufficient  authority  to  act  and  a  better  understanding  of 
the  conditions  and  point  of  view  of  the  farmers  which  comes  from 
his  more  direct  contact  with  them.  An  understanding  of  ditch 
operation  and  the  handling  of  water  from  actual  experience  is 
practically  essential  for  such  positions.  This  can  be  obtained 
most  directly  from  actual  experience  in  ditch  riding. 

DITCH    RIDERS 

The  most  important  as  well  as  the  most  numerous  part  of  the 
operation  force  are  the  ditch  riders.  These  are  the  members  of 
the  operation  force  who  come  into  daily  contact  with  the  farmers, 
the  deliverymen  who  are  constantly  in  touch  with  the  customers. 

Various  names  are  used  for  these  employees  handling  the 
patrolling  of  the  canals  and  the  delivery  of  water.  Among  these 
are  the  terms  ditch  rider,  ditch  tender,  zanzero,  patrolman,  and 
ditch  walker.  The  first  three  are  more  generally  used  where  the 
duties  of  delivery  are  relatively  more  important  than  the  observa- 
tion of  the  canal ;  the  last  two  are  applied  to  those  watching  canals 
for  purposes  of  maintenance  rather  than  delivery. 

The  work  of  ditch  riders  can  be  measured  in  terms  of  the 
irrigable  or  irrigated  area  handled,  the  miles  of  canal  covered,  or 
the  number  of  farms  or  turnouts  served.  With  the  wide  varia- 
tions of  conditions  on  different  systems  the  work  accomplished 
naturally  varies  materially.  Where  the  irrigated  farms  are 
scattered  or  where  the  irrigated  area  per  farm  is  small  as  in  the 
first  years  of  operation  of  new  systems,  the  length  of  ditch  to  be 
ridden  will  more  largely  determine  the  beats  rather  than  the  area 
actually  irrigated.  Where  small  irrigation  heads  are  delivered  to 


86 


IRRIGATION  SYSTEMS 


TABLE  VII. — SUMMARY  OF  THE  WORK  OF  DITCH  RIDERS 
For  Systems  Delivering  to  Individuals 


Number  of 
records 


Irrigated  area  handled  per  ditch  rider, 
acres 


Average 


Minimum         Maximum 


Area  irrigated  per  mile  of  canal 


Less  than  50  acres. 

50  to  75    acres. .  . 

75  to  100  acres 12 

100  to  150  acres 12 

150  to  200  acres 7 

Over  200  acres 3 

Mean 52 

Per  cent,  of  area  irrigable  which 
was  actually  irrigated 

Less  than  30 7 

30  to  40 4 

40  to  50 9 

50  to  60 8 

60  to  80 8 

80  to  100 5 

Mean .  41 

Number  of  farms  per  mile  of  canal 

Less  than  1 4 

1  to  2 11 

2  to  3 11 

3  to  4 7 

4  to  6. , 

Over  6 9 

Mean 50 

Average  area  irrigated  per  farm 

Less  than  20  acres 

20  to  30  acres 

30  to  40  acres 13 

40  to  60  acres 10 

Over  60  acres. . 

Mean 53 

Average    number    of    farms    per 
ditch  rider. . 

Less  than  25 7 

25  to  50 .  18 

50  to  75 14 

Over  75 15 

Mean 54 

Length  of  canal  in  miles  per  ditch 
rider. 

Less  than  15 13 

15  to  20 18 

20  to  25 14 

Over  25 10 

Mean 55 


850 
1,560 
1,750 
2,300 
2,750 
2,970 


550 
420 
1,090 
1,400 
1,250 
2,700 


1,500 
3,000 
2,550 
3,400 
4,000 
3,360 


1,900 


780 
1,240 
1,490 
1,990 
2,350 
3,110 


420 
550 
1,090 
1,600 
1,250 
1,770 


1,800 


1,330 
1,720 
1,940 
3,100 
3,000 
4,000 


720 
1,610 
1,780 
2,350 
3,310 
2,220 


530 

1,030 

550 

420 

1,500 

1,000 


865 
2,440 
3,110 
4,000 
3,400 
3,700 


1,900 


1,510 
1,860 
2,030 
2,200 
2,360 


420 
1,250 

650 
1,090 

630 


3,000 
3,360 
3,500 
4,000 
4,500 


1,970 


1,000 
1,980 
2,340 
2,330 


630 

420 

1,250 

1,250 


2,040 


1,600 
4,000 
4,500 
3,550 


1,480 
1,890 
1,980 
2,330 


420 

730 

630 

1,330 


2,840 
3,400 
4,000 
3,000 


1,900 


OPERATION  AND  MAINTENANCE  87 

small  farms  at  short  intervals,  the  length  of  ditch  and  area  served 
per  ditch  rider  will  usually  be  relatively  small.  Whether  the 
main-canal  organization  delivers  to  individual  or  to  lateral  asso- 
ciations affects  the  work  of  the  main-canal  ditch  riders  very 
materially. 

Area  Handled  per  Ditch  Rider. — In  the  preceding  tables, 
summaries  of  the  practice  of  many  systems  are  given.  These 
include  both  private  and  government  projects  and  are  typical 
of  general  conditions.  Where,  however,  the  individual  examples 
forming  each  mean  vary  as  widely  as  they  do  in  these  cases,  the 
resulting  means  can  be  taken  only  as  relative  tendencies  rather 
than  as  exact  figures.  About  two-thirds  of  the  data  were  taken 
from  the  various  reports  of  systems  of  the  U.  S.  Reclamation 
Service  for  different  years;  the  remainder  include  other  forms  of 
organizations  scattered  through  all  the  States.  Table  VII  gives 
the  data  for  delivery  to  individuals,  Table  VIII  that  for  delivery  to 
the  heads  of  laterals  only. 

Delivery  to  Individuals. — For  delivery  to  individuals  any  con- 
dition which  reduces  the  area  irrigated  per  mile  of  canal  will 
reduce  the  area  served  per  ditch  rider.  This  is  shown  in  the 
first  comparison  of  Table  VII,  the  area  increasing  consistently 
with  the  area  irrigated  per  mile  of  canal.  Where  canals  can  be 
run  on  ridges  or  downslopes,  so  that  deliveries  can  be  made  to  both 
sides,  the  area  handled  per  ditch  rider  will  be  larger  as  the  patroll- 
ing the  ditches  is  relatively  less  in  amount.  This  is  also  shown  in 
the  second  comparison.  When  only  a  small  per  cent,  of  the  land 
covered  is  actually  irrigated,  the  area  irrigated  per  mile  of  canal 
will  be  small,  thus  reducing  the  area  served  per  rider.  The  data 
for  this  comparison  are  taken  entirely  from  systems  of  the  U.  S. 
Reclamation  Service  as  the  records  for  other  systems  did  not 
give  the  irrigable  area  separately.  These  figures  indicate  that  one 
ditch  rider  should  be  able  to  handle  from  2,500  to  3,000  acres  on 
well-developed  systems  under  usual  methods  of  delivery.  In  the 
earlier  years  the  length  of  canal  patrolled  becomes  a  better  crite- 
rion of  the  work  of  the  ditch  riders  as  such  patrolling  is  relatively 
more  important  than  the  delivery  of  water.  The  area  handled 
per  ditch  rider  is  increasing  on  these  systems  as  the  projects 
become  more  fully  developed.  On  13  projects  in  1912,  the  aver- 
age irrigated  area  per  ditch  rider  was  1,415  acres;  for  the  same 
systems  in  1914  it  was  2,020  acres. 

The  comparison  of  number  of  farms  per  mile  seems  to  indicate 


88  IRRIGATION  SYSTEMS 

that  from  three  to  six  farms  per  mile  of  canal  gives  the  balance 
between  area  irrigated  and  size  of  farm  which  is  most  favorable. 
For  fewer  farms  the  effect  of  the  greater  amount  of  riding  per 
delivery  reduces  the  area,  for  more  farms  the  greater  detail  of 
delivering  to  small  holdings  apparently  begins  to  reduce  the  area 
served  per  ditch  rider.  This  latter  condition  does  not  hold,  how- 
ever, where  water  is  delivered  under  rotation  to  small  holdings  at 
relatively  infrequent  periods  such  as  30  days. 

Larger-sized  farms  inean  fewer  turnouts,  and  less  frequent 
changes  in  delivery  resulting  in  larger  areas  served  per  rider  as 
shown  in  the  fourth  comparison.  The  area  served  also  appears  to 
increase  with  the  number  of  farms  up  to  about  50  farms  per  ditch 
rider.  Where  more  than  this  number  are  handled  the  average 
size  apparently  becomes  sufficiently  less  to  balance  the  increase  in 
number. 

The  larger  number  of  farms  are  mainly  for  those  systems  where 
infrequent  deliveries  are  made  or  where  daily  visits  are  not  made 
if  the  delivery  is  continuous.  The  area  served  also  increases  with 
the  length  of  canal  covered  per  ditch  rider.  Where  patrolling  is 
relatively  less  important  and  inspection  of  canals  less  frequent 
more  area  can  be  covered  if  the  method  of  delivery  does  not 
require  daily  visits  to  all  turnouts. 

Of  the  three  methods  of  delivery,  continuous  flow  gives  a 
higher  average  area  served  per  canal  rider  than  either  rotation  or 
delivery  on  demand.  This  does  not  mean  that  for  any  given  sys- 
tem a  change  from  continuous  flow  to  rotation  would  reduce  the 
area  per  rider  but  indicates  that  continuous  flow  is  used  on  sys- 
tems where  the  other  conditions  such  as  large  size  of  farms,  lack  of 
close  control  of  delivery  and  ample  water  supply  are  also  favor- 
able to  large  areas  per  rider.  With  continuous  flow  there  are 
fewer  changes  of  headgates  required.  For  delivery  in  rotation,  if 
the  p>eriod  between  deliveries  is  3  to  4  weeks,  only  a  small  portion 
of  the  farms  will  be  receiving  water  at  any  one  time  and  large 
areas  may  be  handled  if  the  other  conditions  are  favorable.  Where 
the  rotation  period  is  short,  such  as  deliveries  at  alternate  4-day 
periods,  the  frequency  of  changes  may  result  in  smaller  areas  per 
rider  than  under  continuous  flow.  With  delivery  on  demand, 
unless  a  relatively  long  period  of  notice  is  required,  the  ditch  rider 
cannot  plan  his  deliveries  as  far  ahead  and  will  not  usually  be 
able  to  care  for  as  large  an  area.  Where  2  to  4  days  notice  is 
required,  this  disadvantage  may  be  largely  overcome. 


OPERATION  AND  MAINTENANCE  89 

The  measurement  of  the  water  delivered  to  individuals  will  not 
materially  affect  the  area  served  per  ditch  rider.  Where  the 
charges  for  operation  are  based  on  such  measurements,  it  is  desir- 
able that  daily  records  be  secured.  This  may  involve  extra 
visits  to  headgates  in  some  cases,  although  except  for  small  heads 
delivered  continuously,  daily  visits  during  the  times  of  delivery 
are  usual  on  most  systems.  The  actual  reading  and  recording  of 
gages,  openings  and  other  field  notes  in  connection  with  measured 
delivery  will  not  reduce  the  area  in  a  beat  to  any  extent. 

The  extent  to  which  handling  of  headgates  by  the  farmer  is  per- 
mitted affects  the  area  per  ditch  rider.  If  all  gates  are  locked, 
closer  attention  by  the  rider  is  required.  On  the  "Big"  Ditch 
near  Billings,  Mont.,  4  riders  handle  25,000  acres  delivering 
under  continuous  flow  to  individuals  and  some  laterals  which  are 
usually  small.  This  system  consists  of  a  main  canal  about  40 
miles  long,  having  good  wasteway  facilities.  Each  farmer  or 
group  of  farmers  operate  their  own  headgates  as  long  as  they  do 
not  take  water  in  excess  of  the  amount  to  which  their  shares 
entitle  them.  The  ditch  rider's  duties  consist  mainly  in  patrolling 
the  ditch,  regulating  headgates  taking  a  noticeable  excess,  and 
regulating  the  canal  flow  at  the  wasteways.  This  method  gives  a 
very  low  cost  of  operation  for  the  system;  if  the  value  of  the  time 
spent  by  each  farmer  in  visiting  his  headgate  was  included,  the 
total  cost  of  service  might  be  greater  than  on  other  systems  more 
closely  controlled. 

The  numerical  comparisons  given  in  Table  VII  are  made  by 
separating  data  according  to  a  single  variable  where  the  actual  re- 
sult depends  in  each  case  on  the  combined  effect  of  a  number  of 
variables.  Within  any  given  project,  the  area  served  by  different 
ditch  riders  will  vary  as  the  conditions  on  the  different  parts  of  the 
system  vary.  It  appears,  however,  that  the  following  generali- 
zations are  warranted: 

1.  The  irrigated  area  served  per  ditch  rider  is  most  directly 
affected  by  the  percentage  of  the  land  under  the  canals  which  is 
irrigated. 

2.  The  area  served  increases  with  the  average  size  of  farm,  the 
rate  of  increase  in  area  served  being  less  than  the  increase  in  the 
size  of  the  farm. 

3.  The  area  served  is  not  increased  for  more  than  3  or  4  farms 
per  mile  of  canal. 

4.  The  area  served  is  not  increased  where  each  ditch  rider 


90  IRRIGATION  SYSTEMS 

handles  more  than  50  farms,  the  increase  apparently  being  bal- 
anced by  the  decrease  in  irrigated  area  per  farm. 

5.  Methods  of  delivery  requiring  few  changes  of  headgates, 
such  as  continuous  flow  or  long  rotation  periods,  or  methods  of 
operation  in  which  the  control  of  delivery  is  less  exact,  are  favor- 
able to  large  areas. 

Delivery  to  Laterals  Only. — On  some  systems,  particularly  the 
older  ones,  the  organization  operating  the  main  canals  makes 
delivery  only  to  laterals  or  to  groups  of  farmers  who  attend  to  the 
further  subdivision  of  the  water  among  themselves.  In  such  cases 
the  amount  of  water  in  each  delivery  is  larger  than  for  delivery  to 
individuals  and  the  ditch  riders  on  the  main  canals  can  handle 
much  larger  areas.  On  such  systems  the  irrigated  area  per  main 
canal  ditch  rider  varies  from  4,000  to  10,000  acres  or  more,  de- 
pending upon  the  size  of  laterals.  The  riders  under  the  laterals 
cover  about  the  same  or  a  little  larger  areas  than  those  on  similar 
systems  delivering  directly  to  each  individual,  making  the  total 
delivery  force  somewhat  larger  although  the  organization  of  the 
main  canal  is  much  simpler.  On  other  systems  a  mixed  practice 
is  followed,  deliveries  being  made  directly  to  those  farms  near  the 
main  canals  and  laterals  and  to  lateral  associations  for  the  more 
distant  lands.  This  is  shown  by  the  comparison  given  in  Table 
VIII.  The  number  of  records  for  delivery  to  laterals  is  less  than 
those  given  for  delivery  to  individuals  and  the  means  are  conse- 
quently less  dependable.  The  area  served  increases  with  the  area 
irrigated  per  mile  of  canal  as  this  increases  the  average  size  of 
laterals  to  which  delivery  is  made.  The  effect  of  delivery  to  the 
heads  of  sub-laterals  as  compared  with  delivery  to  individuals  is 
shown  on  the  gravity  unit  of  the  Minidoka  project.  In  1911, 
delivering  to  laterals  each  ditch  rider  handled  an  average  irrigated 
area  of  4,860  acres;  in  1914,  after  the  operation  of  the  laterals 
had  been  taken  over  and  deliveries  were  made  to  each  farm,  the 
average  was  2,650  acres. 

Summary  of  Area  Handled  per  Ditch  Rider. — The  average  area 
irrigated  per  ditch  rider  for  the  58  records  of  delivery  to  indi- 
viduals is  1,870  acres.  As  this  includes  many  new  systems  it  is 
lower  than  the  general  average.  The  average  of  20  records  for 
delivery  to  laterals  only  was  7,200  acres.  The  irrigated  area 
which  a  ditch  rider  may  be  expected  to  handle  under  different  con- 
ditions may  be  summarized  as  follows: 

Less  than  1,000  Acres. — During  the  first  year's  operation  of 


OPERATION  AND  MAINTENANCE 


91 


TABLE  VIII. — SUMMARY  OF  THE  WORK  OF  DITCH  RIDERS 
For  Systems  Delivering  to  Laterals  Only 


Number 
of 
records 

Irrigated  area  handled  per  ditch  rider,  acres 

Average 

Minimum 

Maximum 

Area  irrigated   per   mile  of   canal 
operated 

4 

8 
4 
4 

6,640 
5,780 
7,800 
9,200 

3,550 
3,000 
3,700 
5,670 

10,000 
13,000 
15,000 
12,000 

Less  than  100  acres  
100  to  200  acres  

200  to  400  acres 

Over  400  acres  

Mean 

20 

7,040 

Number  of  farms  per  mile  of  canal 

6 
4 
3 
4 

5,430 
5,510 
9,550 
8,090 

3,000 
3,500 
4,860 
5,670 

10,000 
9,000 
13,000 
1,200 

Less  than  2 

2  to  4  

4  to  6.                       

Over  6 

Mean.                                  .  . 

17 

6,800 

systems  serving  lands  difficult  to  prepare  for  irrigation  where  the 
area  irrigated  per  farm  is  small  or  where  only  a  small  proportion 
of  the  farms  are  actually  irrigated.  For  small  farms  which  re- 
quire frequent  deliveries. 

Between  1,000  and  1,500  Acres. — For  systems  in  which  only 
from  one-third  to  one-half  the  land  is  irrigated;  where  the  pa- 
trolling of  the  canal  is  relatively  more  important  than  the  delivery 
of  water ;  where  the  soils  or  other  conditions  are  variable,  requiring 
variable  periods  between  irrigations  and  variable  sizes  of  irriga- 
tion heads. 

Between  1,500 and  2,000  Acres. — For  systems  in  which  from  one- 
half  to  two-thirds  of  the  area  is  irrigated,  for  systems  supplying 
small  orchard  tracts  with  small  and  closely  controlled  irrigation 
heads;  for  systems  supplying  farms  irrigating  20  to  30  acres  under 
average  conditions. 

Between  2,000  and  2,500  Acres. — For  average  systems  in  which 
from  two-thirds  to  three-fourths  of  the  area  is  irrigated;  where  the 
average  area  irrigated  per  farm  is  over  30  acres;  for  well-con- 
trolled systems  serving  small  orchard  tracts  requiring  relatively 


92  IRRIGATION  SYSTEMS 

infrequent  deliveries;  where  the  average  number  of  turnouts  per 
mile  of  canal  is  three  or  more. 

Between  2,500  and  3,000  Acres. — For  average  systems  well- 
developed;  for  small  sizes  of  farms  with  deliveries  not  as  closely 
controlled  as  in  class  above;  where  area  served  per  mile  of  canal 
exceeds  150  acres;  where  rather  large  irrigation  heads  are  deliv- 
ered under  rotation. 

Between  3,000  and  4,000  Acres. — Systems  delivering  to  small 
laterals,  or  large  farms ;  where  delivery  is  not  as  closely  supervised 
as  in  above  classes  where  large  irrigation  heads  are  delivered  at 
relatively  long  periods  to  well-developed  areas. 

Between  4,000  and  4,500  Acres. — Systems  requiring  less  detail 
supervision  of  delivery,  such  as  allowing  the  users  considerable 
latitude  in  regulating  their  gates;  delivery  to  small  laterals  or 
group  ditches;  systems  requiring  infrequent  changes  of  delivery 
such  as  continuous  flow  to  large  farms  in  compact  areas. 

Between  5,000  and  7,500  Acres. — For  delivery  to  individuals 
only  under  the  most  favorable  conditions,  such  as  compact  well- 
developed  areas  of  large  farms  requiring  little  control  of  delivery ; 
for  delivery  to  medium-sized  laterals  requiring  only  average 
supervision. 

Over  7,500  Acres. — For  delivery  to  relatively  large  laterals 
where  area  served  per  mile  of  main  canal  is  relatively  large. 

Length  of  Beats. — The  length  of  canal  patrolled  by  a  ditch 
rider  depends  on  the  relative  importance  of  maintenance  and  of 
water  delivery.  For  canals  with  ample  freeboard  or  few  danger- 
ous locations,  patrolling  the  entire  length  each  day  may  not  be 
necessary.  Where  canals  are  carried  across  flat  lands  with  the 
water  surface  held  above  the  lands  on  both  sides,  daily  patrolling 
of  each  bank  may  be  needed.  The  average  length  of  canal  per 
beat  of  the  same  systems  used  in  the  discussion  of  the  area  irri- 
gated per  ditch  rider  was  20  miles  for  delivery  to  individuals  and 
25  miles  for  delivery  to  laterals  only.  The  less  detail  required  in 
delivery  to  laterals  appears  to  enable  the  ditch  rider  to  cover  a 
somewhat  greater  average  length  of  canal. 

The  number  of  farms  served  per  ditch  rider  varies  widely.  For 
small  orchard  tracts  of  10  to  20  acres  irrigated  under  rotation  at 
30-days  intervals,  conditions  typical  of  a  number  of  southern 
California  systems,  from  100  to  300  tracts  may  be  served  per 
ditch  rider,  the  average  of  several  systems  being  about  175.  For 
delivery  to  laterals,  the  total  number  of  farms  depends  on  the  size 


OPERATION  AND  MAINTENANCE  93 

of  the  laterals  and  may  exceed  300  on  some  systems.  The  average 
for  the  system  of  the  U.  S.  Reclamation  Service  has  been  about 
50  farms  per  rider  for  delivery  to  individuals  and  about  110  for 
delivery  to  laterals.  These  figures  are  probably  representative  of 
average  conditions  in  the  mountain  States  where  the  individual 
farms  have  an  average  size  of  over  40  acres  or  for  delivery  to  sub- 
laterals  serving  only  a  few  farms. 

Compensation  of  Ditch  Riders.2 — The  pay  of  ditch  riders  varies 
with  the  conditions  of  service.  It  is  usual  for  the  rider  to  furnish 
and  maintain  his  own  horses.  Where  motorcycles  or  autos  are 
used  they  are  generally  supplied  by  the  company.  If  the  rider 
furnishes  his  own  horse,  it  will  receive  better  care.  The  company 
may  not  be  able  to  use  such  stock  to  advantage  in  the  non-opera- 
tion season.  In  some  cases,  particularly  on  diversion  canals  or 
other  locations  outside  the  settled  areas,  the  company  may  furnish 
quarters  to  the  rider.  The  usual  rate  of  pay  on  government 
systems  varies  from  $75  to  $90  per  month,  with  an  average  of 
about  $85.  The  pay  is  sometimes  varied  with  the  requirements 
of  the  different  beats,  such  as  $75  per  month  when  1  horse  is 
used  and  $90  when  2  are  needed.  On  other  systems  the  aver- 
age pay  ranges  from  $90  per  month  when  a  horse  is  furnished  by 
the  ditch  rider  to  about  $70  without  the  horse. 

On  systems  having  operating  seasons  of  9  months  or  over,  the 
ditch  riders  may  be  employed  continuously  throughout  the  year, 
being  used  on  maintenance  work  during  the  short  non-operating 
season.  Where  the  winter  seasons  are  closed  and  relatively  long, 
it  is  not  usual  to  carry  the  riders  throughout  the  year,  as  con- 
struction work  cannot  be  carried  on  during  the  winter.  Includ- 
ing fall  and  spring  maintenance  work,  some  of  the  riders  may  be 
carried  for  a  total  of  8  months  in  the  mountain  States.  In  some 
cases  the  number  of  riders  can  be  gradually  reduced  toward  the 
end  of  the  season,  as  the  deliveries  to  be  made  are  less  in  number 
and  the  flow  in  the  canals  is  less,  reducing  the  danger  of  breaks. 
Where  the  riders  can  be  employed  at  maintenance  work  on  their 
beats,  it  may  be  preferable  to  have  this  done  rather  than  to  enlarge 
the  beats  of  some  riders  to  cover  territory  with  which  they  are  not 
familiar. 

In  most  cases,  horses  are  used  for  the  transportation  of  ditch 
riders.  Where  roadways  have  been  made  on  the  top  of  canal 
banks  or  where  public  roads  are  used  instead  of  following  the 
canals,  carts  may  be  used.  Riding  is  usually  preferable  to  driving 


94  IRRIGATION  SYSTEMS 

as  the  ditch  rider  has  a  better  opportunity  to  follow  the  canals 
and  inspect  them.  More  rapid  travel,  such  as  motorcycles,  is 
not  usually  desirable  as  the  rider's  attention  is  given  to  the  machine 
rather  than  to  the  ditches.  For  concrete-lined  or  pipe  systems  on 
which  patrolling  is  not  needed,  motorcycles  and  autos  may  be 
used  to  advantage. 

On  a  few  systems  requiring  many  ditch  riders,  inspectors  of 
their  work  have  been  used.  Where  this  is  done  the  better  prac- 
tice is  to  use  such  inspection  for  instruction  to  the  riders  rather 
than  as  a  separate  checking  of  their  records  or  deliveries.  An 
inspector  going  with  the  rider,  advising  him  on  his  methods  of 
measurement,  or  gage  reading,  will  be  of  more  benefit  than  one 
making  separate  readings  for  the  purpose  of  finding  errors.  Such 
duties  of  inspection  are  more  usually  handled  by  the  water 
master  or  superintendent. 

Patrolmen. — On  long  diversion  canals,  patrolmen  may  be  used 
who  make  no  divisions  or  deliveries  of  water.  Such  locations  are 
frequently  along  side  hills  in  which  the  danger  of  breaks  is  rela- 
tively large.  Such  patrolmen  more  usually  walk  their  beats,  as 
the  flumes,  walled  sections  and  other  special  forms  of  construction 
may  make  riding  difficult.  The  usual  beat  consists  of  from  6  to  8 
miles  of  such  canal,  which  is  covered  daily.  In  extremely  bad 
ground  night  patrolling  may  be  used  if  the  canal  is  being  crowded 
to  capacity.  Such  ditch  walkers  also  are  usually  expected  to 
perform  the  routine  maintenance  work  on  their  beat,  such  as 
cleaning  screens,  cutting  weeds  on  the  banks,  and  trapping  or 
otherwise  controlling  burrowing  animals. 

It  is  usual  to  station  a  gate  tender  at  the  diversion  dam  or  head- 
works  and  also  at  larger  reservoirs.  This  is  done  in  order  to 
regulate  the  flow  as  desired  and  to  prevent  injuries  to  structures 
by  drift.  In  some  cases,  such  gate  tenders  may  patrol  an  adja- 
cent section  of  canal. 

ENGINEERING  DIVISION 

With  all  systems  there  is  a  transition  period  between  con- 
struction and  operation  during  which  water  will  be  delivered  to 
some  lands  and  more  or  less  extension  and  structure  work  will  be 
carried  on.  For  such  periods  the  engineering  department  may 
be  more  nearly  that  used  for  construction  than  for  operation. 
The  same  condition  may  exist  during  periods  of  extensive  better- 


OPERATION  AND  MAINTENANCE  95 

ment  work.  Some  engineering  organization  is,  however,  re- 
quired on  systems  on  an  operation  basis  in  order  to  handle  the 
usual  or  routine  engineering  work.  Such  instrument  work  as  the 
location  of  new  structures,  surveys  for  new  laterals  or  extensions, 
drainage  investigations  and  general  miscellaneous  work  will  be 
required.  On  larger  constructions,  particularly  if  done  by  con- 
tract, inspectors  may  be  needed.  Office  drafting  will  include 
routine  map  work,  particularly  during  periods  of  settlement  when 
land  plats  showing  the  status  of  contracts  must  be  kept  up  to  date, 
designs  of  new  structures,  records  of  the  construction  and  loca- 
tion of  new  structures,  and  maps  for  extension  or  drains.  On 
smaller  systems  all  such  work  including  some  hydrographic  obser- 
vations may  be  handled  by  one  man.  On  larger  systems  the 
duties  may  be  sufficient  to  require  separate  instrumentmen,  in- 
spectors and  draftsmen.  During  the  earlier  years  some  systems 
may  furnish  aid  in  locating  farm  ditches,  such  aid  being  handled 
by  the  engineering  force. 

The  hydrographic  work  varies  from  none  to  a  detailed  system 
which  includes  records  of  the  flow  in  all  canals  and  delivery  to 
each  user.  It  is  preferable  to  have  the  hydrography  under  the 
supervision  of  the  engineering  department  although  the  results 
are  secured  from  gage  readings  taken  by  the  operation  force  and 
the  use  of  the  results  is  largely  by  the  operation  division.  It  is, 
of  course,  necessary  that  the  hydrographer  be  in  close  touch  with 
both  the  clerical  and  operating  divisions  and  cooperate  with  them. 
To  secure  such  cooperation  is  part  of  the  duties  of  the  manager. 
In  some  cases  the  clerical  division  may  make  the  routine  computa- 
tions of  the  quantity  delivered.  It  is  preferable,  however,  to 
have  such  computations  made  by  the  hydrographer  and  the  re- 
sults posted  in  the  individual  accounts  by  the  clerical  division. 
The  hydrographic  methods  are  discussed  in  detail  in  Chapter  V. 

The  operation  force  may  become  the  engineering  department  in 
the  non-operating  months.  Except  for  new  work  such  as  ex- 
tensions, structures  are  usually  constructed  outside  of  the  opera- 
tion season.  Ditch  riders  may  become  foremen  and  hydro- 
graphers  instrumentmen.  Such  interchanging  maintains  the 
personnel  intact  throughout  the  year  and  results  in  economy  in 
most  cases  if  the  construction  work  consists  of  many  minor  items 
rather  than  a  few  complex  structures  requiring  special  skill.  The 
opportunity  to  use  part  of  the  operation  force  in  this  way  during 
the  non-operating  season  may  make  it  desirable  to  do  work  by 


96  IRRIGATION  SYSTEMS 

force  account  instead  of  by  contract.  As  a  rule,  however,  it  is 
preferable  to  work  by  contract  where  the  conditions  are  such  that 
definite  specifications  can  be  written,  where  the  quantity  of  work 
to  be  done  is  sufficient  to  furnish  a  good  basis  for  unit  prices,  or 
where  special  equipment  is  required.  This  applies  to  earthwork 
in  masses,  large  flumes  or  other  structures.  On  small  scattered 
structures,  and  general  canal  cleaning,  force  account  methods  give 
good  results. 

CLERICAL   DIVISION 

This  is  the  office  and  accounting  division.  It  is  in  charge  of  the 
secretary  on  cooperative  systems  or  the  chief  clerk  on  government 
systems;  the  title  varies  in  other  cases.  The  accounts  include 
these  discussed  in  Chapter  IX.  There  are  also  the  individual 
accounts  of  each  land  owner  which  may  vary  from  a  single 
seasonal  assessment  to  frequent  entries  covering  charges  for  water 
as  it  is  delivered.  Construction  mess  and  corral  accounts,  ma- 
terial and  stock  records,  correspondence,  and  purchases  are  also 
handled  in  this  division.  The  number  of  clerical  employees 
varies  with  the  size  and  the  character  of  the  ownership  of  the 
system.  For  larger  systems,  the  duties  of  the  different  clerical 
employees  may  be  quite  distinct,  such  as  the  bookkeeper,  material 
clerk  and  purchasing  agent,  in  smaller  systems  the  duties  overlap 
and  one  man  may  handle  all  clerical  matters. 

SIZE  OF  ORGANIZATION 

At  the  1911  Operation  and  Maintenance  Conference  at  Boise, 
a  paper  was  presented  by  Mr.  R.  K.  Tiffany,  then  manager  of  the 
Sunnyside  project,  in  which  a  series  of  organizations  for  different 
sized  systems  were  given  as  shown  in  Table  IX.  As  stated  by 
Mr.  Tiffany  the  number  of  employees  given  would  represent  about 
the  maximum  which  would  be  required.  Under  favorable  con- 
ditions the  number  may  be  materially  reduced  and  many  systems 
are  operated  with  smaller  organizations. 

As  an  instance  of  the  effect  on  the  organization  of  the  main 
canal  system  of  the  delivery  of  water  to  laterals  only  or  to  indi- 
viduals, a  case  on  the  Boise  project  was  cited.  On  32,000  acres, 
of  which  21,000  were  irrigated,  water  was  delivered  to  laterals  only 
on  about  half  of  the  area;  one  water  master,  one  field  clerk,  2 
gate  tenders  and  8  ditch  riders  handled  this  area  at  a  cost  of  5 


OPERATION  AND  MAINTENANCE 

TABLE  IX. — SIZE  OF  ORGANIZATION 


97 


Position 

Size  of  project 

20,000  acres 

50,000  acres 

100,000  acres 

Number  of 
employees 

Monthly 
salary 

Number  of 
employees 

Monthly 
salary 

Number  of 
employees 

Monthly 
salary 

Manager  

1 
1 

$200 
125 

1 
1 
1 
1 
1 

$250 
150 
125 
90 
150 

1 
1 
1 

2  @$90 
1 
1 
2  @$90 
3  @  $150 
40  @  $90 

1 
2  @$90 

$300 
175 
125 
180 
150 
100 
180 
450 
3,600 

90 
180 

Chief  clerk  .... 

Bookkeeper  

Stenographers.  .  . 

Engineer  
Hydrographer.  .  . 

1 

125 

Inspector.  ...    . 

1 

2 
20  @  $90 

100 
275 
1,800 

Water  masters.  .  . 
Ditch  riders  
Telephone     line- 
man 

1 

8  @$90 

125 
720 

Water-record 
clerks  

1 

75 

1 

90 

Total  per  month  . 
Cost  per  acre  per 
month 

$1,370 

6.8   cents 

$3,030 
6    cents 

$5,520 
5.5  cents 

cents  per  acre  per  month.  On  another  division  containing  about 
33,000  acres  of  which  15,000  were  irrigated,  water  was  delivered 
to  each  individual  farm  at  a  cost  of  12%  cents  per  month. 

The  average  size  of  the  clerical  force  for  government  projects 
was  given  as  follows  at  the  same  conference:  up  to  15,000  acres, 
one  clerk;  15,000  to  40,000  acres,  two  clerks;  40,000  to  75,000 
acres,  three  clerks;  75,000  to  120,000  acres,  four  clerks;  120,000 
to  175,000  acres,  five  clerks;  175,000  to  240,000  acres,  six  clerks. 
These  do  not  include  the  keeping  of  the  strictly  operation  or 
water-delivery  records.  It  was  considered  that  one  man  should 
handle  about  2,000  individual  accounts  in  the  books.  For  other 
forms  of  organization  the  clerical  force  is  usually  somewhat 
smaller. 

REFERENCES  FOR  CHAPTER  III 

TIFFANY,  R.  K. — Size  of  Organization  Required  for  Handling  Water  to  an 
Area  of  20,000  to  100,000  Acres,  1911,  First  Conference  of  Operating 
Engineers,  Boise,  Idaho. 

GULLICKSON,   A.   H. — Size  of  Clerical  Force,    1911,    First   Conference  of 
Operating  Engineers,  Boise,  Idaho. 
7 


98  IRRIGATION  SYSTEMS 

Report  of  Committee  on  Organization,  1913,  Conference  of  Operating  Engi- 
neers, Great  Falls,  Mont. 

STOCKTON,  R.  S. — Management  of  Irrigation  Systems,  Engineering  and 
Contracting,  Jan.  28,  1914. 

BLISS,  G.  H. — Organization  for  Irrigation  Operation  and  Maintenance, 
Engineering  and  Contracting,  May  6,  1914. 

RINKER,  G. — Duties  of  Ditch  Riders  and  Methods  of  Inspection  or  Check- 
ing These,  1911,  First  Conference  of  Operating  Engineers,  Boise,  Idaho. 

COLE,  D.  W. — Wherefore  the  Project  Manager,  Reclamation  Record,  July, 
1916. 


CHAPTER  IV 
METHODS    OF    DELIVERING    IRRIGATION    WATER 

The  purpose  of  all  the  methods  of  delivery  used  on  irrigation 
systems  is  to  furnish  to  each  individual  the  quantity  of  water  to 
which  he  is  entitled  at  the  time  at  which  its  use  is  desired.  The 
extent  to  which  this  is  accomplished,  both  in  quantity  and  time, 
measures  the  success  of  the  operation  methods  used.  Under  the 
different  conditions  of  the  use  of  water  and  of  the  water  supply 
which  are  found  on  different  systems,  no  one  general  method  of 
delivery  can  be  expected  to  be  suited  to  all  cases.  The  selection 
of  the  method  to  be  used  on  any  particular  system  should  be  based 
on  a  careful  study  of  such  local  conditions.  On  the  larger  proj- 
ects conditions  within  the  project  may  vary  to  such  an  extent  that 
different  methods  of  delivery  will  be  required  on  different  parts  of 
the  same  project. 

In  the  selection  of  the  delivery  methods  the  farm  needs  are  the 
determining  factor.  The  financial  success  of  the  system  depends 
upon  the  financial  success  of  the  users  and  convenience  and  even 
economy  in  operation  of  the  canals  are  secondary  to  convenience 
and  economy  in  the  use  of  water  on  the  farm.  The  requirements 
of  economy  in  delivery  are  not  necessarily  hi  conflict  with  the  use 
on  the  farm;  where  they  do  differ  the  use  on  the  farm  should  con- 
trol. The  attempt  to  adjust  the  farm  use  to  some  desired  opera- 
tion method  has  always  resulted  in  failure  where  the  method  used 
has  not  fitted  into  the  normal  farm  needs. 

There  are  three  principal  methods  of  delivery  used  in  the  opera- 
tion of  irrigation  systems.  These  are  known  as  (1)  continuous 
flow,  (2)  rotation,  and  (3)  delivery-on-demand.  The  general 
nature  of  each  method  is  indicated  by  its  name.  The  practice  on 
any  given  project  may  be  to  some  extent  a  combination  of 
any  two  of  these  methods,  although  the  elements  of  each  can  be 
distinguished. 

Among  the  factors  which  influence  the  choice  of  the  method  of 
delivery  to  be  used  are  the  character  of  the  soil,  topography,  kind 
and  diversity  of  crops  grown,  extent  and  nature  of  the  water 

99 


100  IRRIGATION  SYSTEMS 

supply,  average  size  of  farm,  length  of  irrigation  season  and 
character  of  the  farmers.  The  character  of  the  soil  affects  the 
method  of  delivery  in  regard  to  the  frequency  of  irrigation  and 
depth  applied  at  each  irrigation.  The  topography  influences  the 
size  of  irrigating  head  which  can  be  used  and  thus  the  rate  at 
which  irrigation  can  be  accomplished.  The  kind  of  crop  in- 
fluences the  seasonal  use  of  water.  The  times  at  which  irrigation 
of  grain  is  needed  are  relatively  short,  and  when  needed,  irrigation 
cannot  be  delayed  without  injury  for  as  long  a  time  as  with  some 
other  crops.  Forage  crops  usually  require  relatively  large 
amounts  of  water  distributed  over  a  relatively  long  growing 
season.  Alfalfa,  being  deep-rooted,  may  permit  a  greater 
variation  in  the  time  of  different  irrigations  and  be  better  adapted 
to  relatively  infrequent  rotation  periods.  Cultivated  crops  are 
not  suited  to  the  use  of  large  irrigation  heads.  Orchards  usually 
require  less  frequent  irrigations,  and  the  time  of  irrigation  is  more 
adjustable  than  with  other  crops.  Crops  such  as  potatoes  and 
sugar  beets  may  require  frequent  irrigations  at  certain  times  dur- 
ing the  season.  Where  the  character  of  the  water  supply  permits 
it,  the  time  of  irrigation  should  be  adjusted  to  the  crop  needs; 
where  water  supplies  such  as  flood  flows  only  are  available,  the 
use  must  be  adjusted  to  the  supply.  The  average  size  of  farm 
determines  the  area  served  per  turnout,  the  length  of  time  re- 
quired to  irrigate  each  farm  and  the  frequency  of  change  in  head- 
gates.  The  length  of  season  is  also  a  factor;  where  the  season  of 
operation  is  long  the  total  saving  due  to  more  efficient  methods  is 
greater.  The  character  of  farmers  is  also  important;  if  experi- 
enced in  irrigation  under  one  method,  it  may  be  more  difficult  to 
secure  a  change  in  methods  than  would  be  the  case  with  new 
irrigators  who  could  be  started  under  the  desired  methods  from 
the  beginning. 

Legal  Definitions. — In  the  earlier  adjudications  of  appropria- 
tion rights,  water  rights  were  defined  in  terms  of  continuous  flow. 
The  rights  of  each  area  of  land  or  of  each  canal  were  expressed  as 
the  right  to  take  water  at  a  certain  rate  when  the  use  was  bene- 
ficial. The  present  laws  in  some  States  define  the  extent  of  the 
water  rights  acquired  by  appropriation  in  terms  of  both  the  maxi- 
mum rate  of  use  and  the  total  quantity  per  acre  which  can  be  used 
in  any  season.  The  continuous-flow  right  is  best  suited  to  the 
conditions  which  were  generally  found  on  the  earlier  systems,  and 
as  these  conditions  are  changing,  it  is  becoming  less  generally 


DELIVERING  IRRI&A'Tfiftf-  WATER :         "  101 

desirable  than  formerly.  Provisions  are  now  made  directly  in 
the  laws  of  some  States  and  also  in  the  decrees  of  some  of  the 
courts  for  rotation  between  rights  where  the  extent  of  each  right 
is  small,  and  also  for  prorating  the  available  flow  at  times  of  ex- 
treme scarcity  instead  of  a  strict  observance  of  priorities.  The 
Wyoming  statutes  now  provide  (Laws  1909,  Chapter  CVIII 
No.  1): 

"Rotation  among  water  users.  To  bring  about  a  more  economical 
use  of  the  available  water  supply,  it  shall  be  lawful  for  water  users 
owning  lands  to  which  are  attached  water  rights,  to  rotate  in  the  use 
of  the  supply  to  which  they  may  be  collectively  entitled;  or  a  single 
water  user,  having  lands  to  which  water  rights  of  a  different  priority 
attach,  may  in  like  manner  rotate  in  use,  when  such  rotation  can  be 
made  without  injury  to  lands  enjoying  an  earlier  priority." 

The  Idaho  Supreme  Court  (Helphrey  vs.  Perrault,  86  Pac.,  417) 
has  expressed  itself  as  follows: 

"Rotation  in  irrigation  undoubtedly  tends  to  conserve  the  waters 
of  the  State  and  to  increase  and  enlarge  their  duty,  and  service  and  is 
consequently  a  practice  that  deserves  encouragement  insofar  as  it  may 
be  done  within  legal  bounds." 

In  a  later  case  (State  vs.  Twin  Falls  Canal  Co.,  121  Pac.,  1939), 
in  discussing  the  contracts  which  contained  a  clause  that  delivery 
would  be  made 

"according  to  such  rules  and  regulations  based  upon  a  system  of 
distribution  of  water  to  the  irrigators  in  turn  and  by  rotation  as  will 
best  protect  and  serve  the  interests  of  all  the  users  of  water  from  this 
canal  system," 

the  same  court  states: 

"The  rotation  system  is  recognized  by  the  leading  writers  on  irriga- 
tion and  irrigation  engineering  as  a  most  efficient  and  desirable  method 
and  as  producing  the  highest  duty  of  water  of  any  method  of  use." 

And  again: 

"If  each  user  cannot  secure  sufficient  water  for  the  irrigation  of  his 
land  by  a  constant  flow  of  his  proportionate  share  of  the  water  in 
said  canal,  but  can  receive  sufficient  by  rotation,  that  system  should  be 
used." 

On  any  given  project  a  combination  of  all  of  these  various 
factors  may  be  found.  Where  the  conditions  under  any  system 
vary  to  the  greatest  extent,  the  method  of  delivery  used  will  need 


102  IRRIGATION  SYSTEMS 

to  be  the  most  irregular.  Where  the  conditions  are  most  uniform, 
some  definite  system  of  delivery  can  be  developed  which  will  give 
both  economy  in  operation  and  satisfaction  in  use.  The  methods 
suited  to  small  systems  largely  in  one  type  of  crop  may  be  totally 
unsuited  to  a  larger  system  having  variable  soils,  topography  and 
crops. 

CONTINUOUS  DELIVERY 

This  method  is  used  to  a  large  extent  on  the  systems  in  several 
of  the  Rocky  Mountain  States.  A  continuous-flow  method  does 
not  mean  that  use  is  actually  continuous.  The  right  to  secure 
water  when  needed  is  continuous.  The  actual  use  is  usually 
intermittent,  depending  on  the  varying  conditions  on  each  farm. 
The  canal  capacities  must  be  sufficient  to  either  deliver  the  total 
amount  of  all  continuous-flow  rights  equal  to  the  maximum 
total  demand  which  can  be  made  or  for  such  proportion  of  this 
maximum  demand  as  judgment  and  experience  indicate  will  occur 
at  any  given  time.  This  usually  results  in  making  the  sub- 
laterals,  and  sometimes  the  laterals,  of  a  capacity  equal  to  the 
total  rights  under  them  and  in  making  the  main  canals  of  some- 
what less  capacity.  Where  the  crops  are  mainly  of  one  kind, 
there  may  be  periods  during  the  season  when  nearly  all  lands  will 
desire  their  full  flow. 

The  continuous-flow  method  is  best  suited  to  large  farms  or  to 
topographic  conditions  which  make  the  use  of  small  irrigating 
heads  necessary.  On  large  farms  what  may  be  continuous 
delivery  from  the  turnout  becomes  on  the  farm  a  system  of  rota- 
tion between  the  different  fields  of  the  farm.  For  farms  under 
conditions  of  irrigation  which  may  limit  the  irrigation  head  which 
one  man  can  efficiently  handle  to  2  second-feet,  a  condition  quite 
usual  in  the  mountain  States,  20  days  would  be  required  to  cover 
160  acres  to  an  average  depth  of  6  inches.  If  a  farm  of  this  size 
consists  of  some  grain  and  cultivated  crops  with  the  greater  pro- 
portion in  forage,  more  usually  alfalfa,  there  will  be  some  months 
of  the  season  when  practically  continuous  use  of  the  water  will  be 
required.  For  similar  farms  of  smaller  size,  rotation  between  the 
farms  may  be  practiced.  Rotation  on  a  160-acre  farm  where  only 
small  heads  can  be  used  would  require  the  use  of  two  irrigators  for 
about  half  the  time  which  may  be  less  efficient  from  a  farm  labor 
standpoint  than  one  irrigator  all  the  time. 

Where  soil,  topography  or  crop  conditions  reduce  the  size  of 


DELIVERING  IRRIGATION  WATER  103 

irrigation  head  so  that  the  stream  that  can  be  handled  becomes 
small  in  proportion  to  the  size  of  the  farm,  continuous-flow 
methods  of  delivery  are  preferable.  An  extreme  condition  of  this, 
character  is  found  in  some  parts  of  the  foothill  regions  in  Cali- 
fornia where  streams  as  small  as  3  or  4  miner's  inches  are  delivered 
to  small  irrigated  farms.  Furrow  methods  of  irrigation  are  used. 
By  adjusting  the  number  of  furrows  in  use  at  any  time  to  the  size 
of  the  stream  received,  good  efficiency  in  application  can  be  ob- 
tained. Continuous-flow  delivery  is  also  adapted  to  truck  and 
small  fruit  crops  which  during  certain  seasons  of  their  growth  re- 
quire water  at  very  short  intervals  and  for  which  only  small  heads 
can  be  used.  Where  the  conditions  are  such  that  irrigation  heads 
relatively  large  in  proportion  to  the  size  of  the  farm  can  be  used, 
either  of  the  other  methods  of  delivery  is  preferable. 

The  operation  of  the  canals  under  continuous-flow  delivery  is 
usually  easier  than  for  either  rotation  or  demand  delivery. 
There  is  less  fluctuation  in  use.  By  maintaining  the  water  sur- 
face at  proper  heights  above  the  outlets  so  that  the  requisite  quan- 
tities will  be  delivered  at  each  farm,  little  canal  regulation  may  be 
required.  At  the  beginning  and  end  of  the  season,  when  the  use 
of  water  is  more  irregular,  regulation  of  both  the  canals  and  turn- 
outs will  be  required  as  the  demand  varies.  Such  a  system  of 
delivery  is  particularly  suited  to  canals  having  good  water  rights 
to  direct  flow  in  the  stream  and  where  the  water  is  available  when 
its  use  is  desired.  If  the  canals  are  short  or  are  provided  with 
adequate  wasteway  facilities,  so  that  water  not  used  can  be  readily 
disposed  of,  the  continuous-flow  method  of  delivery  permits  a 
more  simple  system  of  operation  than  either  of  the  other  methods. 
Continuous-flow  delivery  is  used  on  the  majority  of  canal  systems 
in  Wyoming,  Montana  and  western  Colorado  and  to  a  large 
extent  in  other  mountain  States. 

ROTATION  DELIVERY 

There  are  many  variations  in  rotation  methods  of  delivery, 
but  the  main  purpose  in  all  cases  is  the  same.  This  purpose  is  the 
delivery  of  relatively  large  irrigation  heads  for  relatively  short 
periods  of  time.  In  practice  it  varies  from  the  delivery  to  any 
farm  for  from  one-thirtieth  to  one-half  of  the  total  time.  It 
may  be  handled  ori  a  fixed  schedule  arranged  in  advance  of  the 
season  and  strictly  adhered  to,  or  it  may  consist  merely  of  in- 


104  IRRIGATION  SYSTEMS 

formal  trading  of  water  arranged  between  individual  users  at 
different  times  during  the  season.  This  latter  practice  often 
occurs  on  systems  which  are  operated  on  general  continuous-flow 
methods. 

The  advantages  to  the  farmer  of  the  rotation  method  are  the 
reduction  in  labor  cost  of  applying  water  to  the  land,  and  the 
smaller  amounts  of  water  required  to  cover  the  land  when  large 
irrigation  heads  are  used.  This,  of  course,  implies  that  the  con- 
ditions are  such  that  relatively  large  heads  can  be  handled  on  the 
land;  the  use  of  larger  irrigation  heads  than  can  be  effectively 
handled  results  in  an  excess  amount  of  surface  waste.  If  crop  or 
topographic  conditions  limit  the  size  of  irrigation  head  which  can 
be  used  to  a  size  which  requires  its  use  for  a  large  proportion  of 
the  season  to  irrigate  the  average  size  of  farm,  the  advantages  of 
rotation  delivery  are  largely  lost. 

Rotation  Schedules. — The  rotation  period  varies  with  different 
systems.  From  an  operation  standpoint,  the  greatest  advantages 
are  secured  when  the  period  between  deliveries  to  each  farm  is 
made  relatively  long.  The  period  can  be  made  the  longest  on 
those  systems  where  the  irrigated  area  consists  largely  of  one 
crop  which  requires  water  at  fairly  regular  but  not  frequent 
intervals.  This  condition  is  found  for  orchards  in  southern 
California  where  irrigations  at  intervals  of  30  days  are  usual,  with 
some  as  long  as  45  or  even  60  days.  Water  rights  there  are  often 
expressed  in  terms  of  the  continuous  flow  of  a  certain  fraction  of  a 
miner's  inch  per  acre.  This  is  allowed  to  accumulate  until  water 
can  be  taken  for  from  1  to  3  days  at  a  rate  which  will  give  the 
desired  size  of  irrigation  head.  One  owning  10  acres  might  receive 
60  miner's  inches  for  1  day  per  month  or  30  miner's  inches  for  2 
days  per  month. 

The  same  conditions  of  fairly  regular  and  relatively  infrequent 
irrigations  are  found  for  the  deeper-rooted  forage  crops,  particu- 
larly alfalfa,  where  the  soil  conditions  are  such  that  moisture  is 
retained  within  reach  of  the  plant  roots.  This  condition  exists 
in  many  parts  of  the  San  Joaquin  and  Sacramento  Valleys  in 
California  where  alfalfa  is  the  predominating  crop,  comprising 
from  60  to  75  per  cent,  of  the  irrigated  area  under  several  systems. 
The  topographic  conditions  are  such  that  irrigation  heads  of  from 
10  to  even  20  second-feet  may  be  handled.  Rotation  schedules 
on  such  systems  are  based  on  the  alfalfa,  water  being  delivered 
for  from  20  minutes  to  1  hour  per  acre  irrigated  at  each  run,  the 


DELIVERING  IRRIGATION  WATER  105 

time  varying  with  the  size  of  irrigation  head  delivered,  so  as  to 
give  an  average  depth  per  irrigation  of  from  6  to  8  inches.  The 
time  between  irrigations  varies  with  the  soil  types;  for  medium 
types  of  soil  or  for  light  soil  on  which  ground  water  is  retained 
within  reach  of  the  roots,  periods  as  long  as  30  days  may  be  used. 
Where  the  soil  is  light  without  any  impervious  layer  or  ground 
water  near  the  surface,  or  for  very  heavy  soils  into  which  only 
small  amounts  of  water  can  be  made  to  enter  at  each  irrigation, 
periods  between  irrigations  as  short  as  12  to  14  days  may  be 
needed.  On  the  Salt  River  project  in  Arizona,  where  the  propor- 
tion of  alfalfa  is  somewhat  less,  the  area  in  cereals  and  cotton 
being  relatively  larger,  the  usual  schedule  provides  deliveries  at 
periods  of  8  days,  continuing  for  from  24  to  48  hours  for  each  160 
acres,  a  10-second-foot  head  being  used.  Where  alfalfa  predomi- 
nates, the  remaining  crops  may  be  irrigated  with  separate  smaller 
heads.  These  may  be  run  independently  of  the  alfalfa  heads; 
some  additional  water  may  be  run  at  the  same  time  as  the  alfalfa 
head  and  delivered  to  such  other  crops  on  farms  adjacent  to  those 
irrigating  alfalfa;  or,  at  certain  times,  such  as  Saturday  of  each 
week,  the  alfalfa  heads  may  be  divided  and  small  heads  delivered 
to  all  farms  for  the  miscellaneous  crops.  Such  other  crops  usually 
consist  of  orchards,  vines  and  gardens  irrigated  by  furrows  where 
irrigation  heads  larger  than  from  2  to  5  second-feet  cannnot  be 
handled.  Where  the  other  crops  consist  more  largely  of  cereals, 
more  frequent  deliveries  with  relatively  large  irrigation  heads  for 
sufficient  time  to  irrigate  only  a  portion  of  each  farm  are  more 
usual. 

In  the  Rocky  Mountain  States  the  crops  on  any  farm  are  usu- 
ally more  diversified  and  each  farm  requires  water  at  more  frequent 
intervals.  Also,  the  farms  are  larger  and  the  topographic'  con- 
ditions are  frequently  such  as  to  prevent  the  use  of  large  irrigation 
heads.  These  conditions. make  it  necessary  that  water  be  deliv- 
ered to  each  farm  for  about  one-half  the  time  and  that  the  period 
between  deliveries  be  relatively  short.  This  may  be  accom- 
plished by  the  delivery  for  half  the  time  of  irrigation  heads 
about  twice  as  large  as  the  average  rate  of  use.  The  periods  of  de- 
livery usually  vary  from  4  days  on  and  4  days  off  to  delivery  on 
alternate  weeks.  Where  much  grain  is  raised,  the  farmers  may 
prefer  the  shorter  periods,  particularly  for  the  part  of  the  season 
in  which  grain  is  irrigated.  The  delivery  on  alternate  weeks  is 
used  on  a  considerable  number  of  projects.  The  shorter  period 


106  IRRIGATION  SYSTEMS 

may  be  desirable  in  the  earlier  years  of  a  system,  the  time  being 
lengthened  as  the  lands  become  better  prepared  and  the  farming 
practice  better  planned  and  organized.  The  rotation  used  may 
be  varied  on  different  parts  of  the  same  system.  On  the  Tie  ton 
project  in  Washington,  a  rotation  schedule  based  on  the  delivery 
of  1  second-foot  to  each  40  acres  for  7  days  out  of  each  21  is  used 
on  the  less  steep  lands  where  larger  heads  can  be  handled.  On 
the  steeper  and  more  shallow  lands,  a  schedule  based  on  1  second- 
foot  to  60  acres  for  7  days  out  of  each  14  is  used,  more  frequent 
and  lighter  irrigations  being  needed.  All  land  under  this  system 
has  relatively  steep  slopes,  so  that  only  small  irrigation  heads  can 
be  used.  On  the  Bear  River  canal  in  Utah,  water  is  delivered  to 
all  users  1  hour  per  week  for  each  acre,  the  irrigation  heads  being 
about  2  second-feet.  A  fixed  schedule  is  used,  being  adjusted 
each  year  so  as  to  equalize  night  and  Sunday  use.  On  the  Flat- 
head  project  of  the  U.  S.  Reclamation  Service  7-day  periods  are 
used.  On  the  North  Platte  and  Huntley  projects,  4-day  periods 
have  been  found  to  be  satisfactory. 

Rotation  Between  Laterals. — The  rotation  method  may  be 
arranged  to  rotate  the  delivery  among  farms  on  the  laterals,  or  it 
may  be  arranged  to  rotate  the  flow  between  different  laterals. 
For  the  first  case,  sufficient  area  to  use  a  rotation  head  continu- 
ously may  be  arranged  on  a  lateral  and  the  water  rotated  be- 
tween the  farms  in  the  area.  Such  a  method  gives  continuous 
flow  in  the  laterals.  For  the  second  case,  a  sufficient  number  of 
irrigation  heads  may  be  turned  into  a  lateral  to  completely  irri- 
gate the  lands  under  it  in  perhaps  one-half  the  time  of  the  rotation 
period.  These  irrigation  heads  would  then  be  turned  into  other 
laterals,  each  lateral  being  dry  for  part  of  the  time.  This  gives 
a  rotation  in  flow  between  laterals,  as  well  as  between  farms,  and 
is  sometimes  known  as  the  periodic  method  of  delivery.  This 
second  method  has  both  advantages  and  disadvantages.  It  has 
the  disadvantages  that  laterals  of  larger  capacity  are  required; 
the  life  of  wooden  structures  may  be  reduced,  due  to  alternate 
drying  and  wetting;  it  is  inconvenient  where  laterals  are  depended 
upon  for  stock  water,  although  a  small  stock  stream  may  be  run 
continuously;  the  liability  of  breaks,  particularly  those  resulting 
from  burrowing  animals,  is  greater  than  where  water  is  main- 
tained continuously  in  the  lateral;  and  there  is  danger  of  erosion 
and  bank  slipping,  if  laterals  of  much  size  are  rapidly  filled  or 
emptied.  The  rotation  between  laterals  has  the  advantage  that 


DELIVERING  IRRIGATION  WATER  107 

the  area  from  which  canal  seepage  occurs  is  reduced ;  where  aquatic 
growths  occur,  the  drying  between  periods  of  use  tends  to  kill  such 
plants,  and  delivery  can  be  more  conveniently  handled,  as  those 
laterals  not  in  use  do  not  need  to  be  patrolled  and  the  area  handled 
per  ditch  rider  may  be  greater.  The  disadvantages  mentioned 
will  usually  make  it  preferable  to  operate  continuously  all  laterals 
having  a  capacity  of  over  40  second-feet,  and  on  systems  deliver- 
ing relatively  small  irrigation  heads  laterals  smaller  than  this 
would  be  used  continuously. 

Delivery  Up  or  Down  Laterals. — When  water  is  delivered  from 
any  lateral  under  rotation  methods,  the  head  may  be  run  through 
to  the  lower  end  of  the  lateral,  and  delivery  made  in  order  up  the 
ditch,  or  delivery  may  be  begun  at  the  upper  end  and  carried 
through  in  order  down  the  lateral.  Both  methods  are  used  on 
different  systems. 

Delivery  down  the  lateral  is  usually  preferable  where  all 
changes  are  made  by  the  ditch  rider.  Such  conditions  occur 
where  deliveries  are  not  made  for  less  than  24-hour  periods  and 
where  water  is  turned  both  on  and  off  by  the  riders.  This  is 
usual  only  where  relatively  small  irrigation  heads  are  used  or 
where  the  farms  are  relatively  large.  It  also  has  the  advantage 
that  those  past  whose  turnouts  the  water  is  being  carried  have 
received  their  supply  and  there  is  less  temptation  for  them  to  take 
water  out  of  turn.  On  closely  handled  systems,  taking  water  out 
of  turn  should  not  occur  under  either  method.  In  rotating  down  a 
lateral  it  is  also  more  convenient  to  serve  any  turnouts  which  for 
any  reason  have  been  missed  in  the  regular  turns.  Turnouts  to 
which  delivery  has  been  made  can  be  locked  and  those  further 
down  on  the  lateral  left  unlocked.  Each  man  can  then  take 
whatever  water  reaches  his  headgate. 

If  delivery  is  made  in  rotation  up  the  lateral,  the  ditch  rider 
can  supervise  the  filling  of  the  lateral  and  the  proper  setting  of  all 
checks.  The  closing  of  turnouts  and  taking  of  water  by  those 
next  in  turn  can  then  be  largely  handled  by  the  users  themselves 
if  only  one  irrigation  head  is  run  in  the  lateral.  The  handling  of 
turnouts  by  the  users  is  of  particular  advantage  where  large  heads 
are  used  and  delivery  to  each  farm  may  be  made  for  only  a  few 
hours.  Permitting  such  changes  removes  the  necessity  for  night 
riding  of  the  laterals.  No  one  should  be  permitted  to  turn  water 
back,  however,  at  any  time,  without  arranging  for  it  to  be  taken 
by  someone  else. 


108  IRRIGATION  SYSTEMS 

If  a  break  occurs  on  the  lateral  while  rotating  up,  delivery  can 
be  made  to  some  farm  above  the  break  without  having  to  turn  the 
water  back  into  the  main  lateral.  In  rotating  down  the  lateral, 
all  farms  above  will  have  been  irrigated  and  such  water  would  be 
wasted,  even  if  turned  out  to  upper  farms.  In  rotating  up  a 
lateral,  no  time  need  be  lost  between  turns;  the  ditch  is  filled 
before  delivery  begins.  In  rotating  down  the  lateral,  there  will 
be  some  time  lost,  which  if  allowed  for  makes  the  times  irregular 
and  if  not  allowed  for  may  be  an  item  for  dissatisfaction  when 
turnouts  are  some  distance  apart.  When  the  lands  are  only 
partly  in  use,  as  in  the  first  few  years  of  operation  of  projects, 
and  the  turnouts  may  be  some  distance  apart,  rotating  up  the 
lateral  may  cause  more  waste  if  water  is  not  taken  for  any  reason 
after  it  has  been  run  down  the  lateral. 

In  general,  rotation  down  the  lateral  is  preferable  where  the 
periods  of  delivery  are  multiples  of  24  hours  or  where  the  laterals 
are  relatively  small  and  easily  regulated.  Rotation  up  the  lateral 
is  preferable  where  the  time  of  delivery  to  each  turnout  is  short 
and  where  breaks  in  the  lateral  are  liable  to  occur. 

Fixed  and  Flexible  Rotation  Schedules. — The  rotation  sched- 
ules may  be  fixed  in  advance  of  the  irrigation  season  and  strictly 
adhered  to,  or  the  deliveries  may  be  made  in  what  amounts  to 
rotation  on  demand  or  in  the  order  of  notice  given  by  the  user. 

With  fixed  rotation  schedules,  each  owner  can  be  notified  of 
the  days  during  the  season  on  which  water  will  be  available  for  his 
use.  Such  methods  are  better  suited  to  crops  such  as  orchards  or 
those  where  irrigation  is  not  definitely  required  within  any  short 
period  of  growth.  For  crops,  such  as  grain,  which  may  require 
water  within  relatively  short  periods  of  time  at  certain  stages  of 
their  growth,  the  actual  time  when  needed  varying  with  the 
climatic  conditions  in  each  year,  prearranged  rotation  schedules 
are  not  suited  unless  the  period  between  deliveries  is  made  quite 
short.  Where  the  conditions  permit  their  use,  a  fixed,  prearranged 
schedule  of  delivery  enables  both  the  operation  to  be  more 
efficiently  planned  and  the  farm  work  to  be  arranged  to  better 
advantage.  Fixed  schedules  should  not  be  adhered  to  so  closely 
but  that  variations  can  be  made  for  unusual  conditions.  If  any 
user  does  not  take  the  water  when  offered  during  any  run,  it  is 
usual  to  have  the  right  to  demand  water  at  that  run  lost.  The 
following  rule  of  the  Turlock  irrigation  district  is  typical  of  usual 
practice : 


DELIVERING  IRRIGATION  WATER  109 

"The  irrigator  who  fails  to  use  his  allotment  of  water  during  an 
irrigation  will  not  be  entitled  to  any  more  water  at  any  future  irriga- 
tion than  if  he  had  used  his  full  share  at  the  time  of  allotment." 

Individual  exchanges  of  turn  are  usually  permitted  where  the 
operation  is  not  interfered  with  or  other  irrigators  injured.  The 
responsibility  of  satisfying  the  one  giving  up  his  turn  is  placed  on 
the  one  securing  the  benefit,  exchanges  of  turn  being  arranged  by 
the  irrigators.  When  interruptions  occur  in  the  schedule,  it  is 
customary  to  advance  the  schedule  for  the  period  of  delay. 

Delivery  During  Shortage. — Rotation  schedules  may  be  ar- 
ranged for  periods  when  water  is  plentiful,  so  as  to  allow  ample 
quantities  of  water  to  each  user.  When  the  water  supply  becomes 
less,  the  schedule  may  be  modified,  either  by  reducing  the  irriga- 
tion head,  the  time  of  each  delivery  or  the  frequency  of  delivery. 
It  is  usually  preferable  to  reduce  the  time  of  each  delivery.  The 
reduction  of  the  size  of  irrigation  head  will  generally  reduce  the 
efficiency  of  its  use.  The  reduction  of  the  time  water  is  delivered 
per  acre  may  reduce  the  area  which  can  be  irrigated  at  each  turn. 
All  laterals  may  be  operated  continuously  during  periods  of 
ample  supply,  with  rotation  between  laterals  used  at  times  of  low 
flow. 

On  the  Sunnyside  project  in  1915,  a  shortage  of  water  was  met 
by  shutting  water  out  of  each  one-ninth  of  the  project  for  2  days, 
in  turn,  which  was  later  changed  to  shutting  water  out  of  each 
one-sixth  of  the  project  for  3  days  in  turn.  As  the  shortage 
increased,  the  supply  in  the  river  was  rotated  with  other  canals, 
the  water  secured  by  the  Sunnyside  project  being  rotated  between 
the  two  parts  of  the  system  in  turn  for  half  of  each  period,  deliv- 
eries being  made  only  to  fruit,  vegetables  and  young  seeding  in 
bad  shape  and  denying  water  to  old  alfalfa  land  or  lands  without 
crop. 

DELIVERY  ON  DEMAND 

Under  this  method  the  user  has  a  right  to  a  certain  rate  of  flow 
or  to  a  total  seasonal  amount  in  acre-feet  which  can  be  taken  on 
demand,  subject  to  such  regulations  as  may  be  necessary  in  the 
operation  of  the  system.  These  necessary  regulations  are  usually 
such  that  the  actual  deliveries  may  be  more  largely  an  informal 
rotation  method,  rather  than  strictly  a  delivery  on  demand.  Any 
approach  to  actually  delivering  on  demand  requires  large  canal 


110  IRRIGATION  SYSTEMS 

capacities  in  proportion  to  the  area  served,  as  well  as  a  water  sup- 
ply available  for  use  at  fluctuating  rates. 

Delivery  on  demand  is  the  simplest  method  from  the  stand- 
point of  the  user.  It  requires  less  judgment  on  the  part  of  the 
irrigator  in*  forecasting  the  water  needs  of  his  crops.  Its  use  is 
quite  general  for  the  earlier  years  of  the  operation  of  a  system 
when  both  the  canal  capacity  and  water  supply  are  in  excess  of  the 
requirements  of  the  small  proportion  of  the  irrigated  area  served 
in  the  first  years.  Where  the  capacity  of  the  canals  is  properly 
proportioned  to  the  area  served,  actual  delivery  on  demand  dur- 
ing times  of  maximum  use  is  impractical  if  irrigation  heads  larger 
than  the  rights  to  continuous  flow  are  used.  For  such  conditions 
some  restrictions  on  the  demands  must  be  used.  This  is  done  by 
requiring  requests  for  delivery  to  be  made  a  certain  time  in  ad- 
vance of  the  desired  use.  Three  days'  notice  is  required  on  many 
systems,  only  1  day  on  others  and  longer  times  on  a  few  systems. 
When  delivery  can  be  made  in  less  time  than  the  period  of  notice, 
it  is  usually  done.  When  the  demands  exceed  the  supply,  the 
period  until  delivery  is  actually  made  may  exceed  the  period  of 
notice,  delivery  being  made  as  rapidly  as  possible  in  the  order  in 
which  the  requests  were  received.  As  the  irrigation  heads  de- 
livered are  usually  similar  in  size  to  those  used  under  rotation 
methods,  this  amounts  to  an  irregular  rotation  method  of  delivery. 

The  rule  governing  delivery  of  Imperial  Water  Co.  No.  1,  has 
been: 

"All  applications  for  water  must  be  in  writing  on  blanks  furnished 
by  the  company  and  must  be  delivered  at  least  3  days  before  the  water 
is  needed.  Efforts  will  be  made  to  make  delivery  in  less  than  3  days 
and  where  possible,  delivery  will  be  made  within  24  hours." 

Delivery  on  demand  is  used  by  the  Santa  Ana  Valley  Irrigation 
Co.  during  the  winter  and  spring  season  when  the  supply  is  large 
in  proportion  to  the  use,  rotation  being  used  during  the  summer. 
The  Bitter  Root  Valley  Irrigation  Co.  in  Montana  delivers  on 
demand  with  a  limitation  that  the  use  in  any  1  month  shall  not 
exceed  6  inches  depth  on  the  land.  The  North  Poudre  canal  in 
Colorado  uses  delivery  on  demand.  As  their  supply  is  secured 
largely  from  storage  near  to  the  lands  irrigated,  the  available 
supply  is  known  relatively  closely  in  advance  and  can  be  prorated 
to  the  land,  to  be  taken  on  demand. 

It  is  an  advantage  to  the  user  to  be  able  to  secure  water  when 


DELIVERING  IRRIGATION  WATER  111 

desired.  Greater  flexibility  in  planning  other  farm  operations  is 
possible  if  the  time  of  irrigation  can  be  adjusted  to  other  farm 
work  and  to  the  needs  of  the  different  crops.  Where  the  water 
supply  is  ample,  the  question  involved  may  be  to  decide  how  far 
the  canal  system  is  justified  in  increasing  the  capacity  of  the 
canals,  so  as  to  be  able  to  more  nearly  deliver  on  demand 
with  its  resulting  high  peak  load  in  comparison  with  the  saving  in 
construction  cost  of  smaller  canals  and  the  resulting  necessary 
restrictions  on  use.  The  conditions  of  water  supply  determine 
canal  capacities  in  many  cases ;  where  the  water  supply  is  secured 
through  storage,  the  question  of  the  maximum  rate  at  which  de- 
livery shall  be  made  is  one  of  maximum  canal  capacity.  Where 
water  is  secured  through  direct  diversion,  the  maximum  rate  of 
diversion  may  be  limited  by  the  character  of  the  stream  flow  or 
of  the  water  right.  Actual  delivery  on  demand  without  re- 
strictions is  possible  only  for  short  canals  delivering  from  streams 
of  ample  flow  or  from  reservoirs.  For  long  canals  or  usual  con- 
ditions of  water  supply,  a  compromise  between  the  desire  to 
deliver  the  peak  demand  and  the  resulting  higher  cost  of  the 
system  is  usual.  Delivery  on  demand  for  long  canals  makes 
desirable  ample  wasteway  facilities,  in  order  to  dispose  of  water 
not  taken  for  use. 

Different  means  of  restricting  the  maximum  rate  of  use  may  be 
used.  The  delivery  in  order  of  request  is  one  of  these  methods. 
Water  rights  may  be  based  on  the  delivery  of  a  certain  number  of 
acre-feet  per  acre  during  the  season  with  a  restriction  on  the 
amount  which  can  be  taken  during  any  1  month.  The  land  may 
be  entitled  to  water  at  a  certain  continuous  rate  of  flow  per  acre, 
such  as  J^o  second-foot.  This  defines  the  maximum  demand 
that  can  be  made  on  the  system.  In  practice,  except  for  large 
farms,  the  water  to  which  two  or  more  farms  are  entitled  may  be 
combined  and  rotated  among  the  farms;  if  such  rotation  does  not 
follow  any  regular  schedule,  it  may  be  practically  a  delivery  on 
demand,  but  is  limited  by  the  maximum  rate  of  use  restrictions. 

From  the  point  of  view  of  the  canal  system,  the  delivery- 
on-demand  method  is  suited  to  systems  serving  crops  such  as 
orchards,  where  the  demand  is  more  uniformly  distributed  through- 
out the  season.  This  is  the  case  for  some  southern  California 
systems,  the  method  being,  in  practice,  a  rotation  in  the  order  of 
demand  rather  than  rotation  by  a  fixed  schedule.  The  method  is 
also  suited  to  systems  where  the  canal  capacity  is  large  in  pro- 


112  IRRIGATION  SYSTEMS 

portion  to  the  area  actually  irrigated.  This  occurs  in  the  first 
year's  operation  of  all  systems.  It  also  occurs  where  the  avail- 
able supplies  are  stored  in  the  vicinity  of  the  land  and  the  storage 
can  be  drawn  on  as  desired.  The  same  condition  favorable  to 
delivery  on  demand  may  exist  for  canals  diverting  from  streams 
of  plentiful  water  supply  and  provided  with  ample  waste  way 
facilities.  This  is  the  case  of  the  "Big"  Ditch  in  Montana  where 
the  system  used  is  a  mixture  of  continuous  flow  and  demand,  each 
user  being  limited  to  his  right  to  continuous  flow  in  times  of  heavy 
use  but  being  generally  able  to  secure  larger  heads  at  other  times. 
In  practice,  delivery  on  demand  is  more  often  an  element  in  the 
use  of  either  of  the  other  methods,  rather  than  a  complete  method 
in  itself. 

SPECIAL  METHODS 

There  may  be  special  forms  of  delivery  which  do  not  fall  into 
any  of  the  three  methods  discussed.  In  a  few  exceptional  cases, 
the  seepage  from  the  canals  may  raise  the  ground  water  suffi- 
ciently high  so  that  surface  application  is  not  needed.  Where 
the  height  of  the  water  table  can  be  controlled,  this  form  of 
subirrigation  has  many  advantages.  Delivery  may  consist  in 
supplying  sufficient  amounts  to  the  canals  or  areas  used  for  seep- 
age, to  maintain  the  water  table.  Delivery  in  such  cases  is  usu- 
ally continuous.  Such  conditions  are  favorable  only  in  porous 
soils  free  from  alkali;  there  are  areas  of  this  character  in  parts  of 
the  delta  region  of  California  and  in  special  areas  in  other  States. 
The  subirrigation  of  one  portion  of  a  system  is  usually  accom- 
panied by  the  water-logging  of  lower  lands. 

In  a  few  systems  delivery  is  made  under  pressure  pipe  lines, 
somewhat  similar  to  water-works  practice.  These  have  been 
used  for  small  areas  in  orchards,  mainly  in  the  coast  States. 
Delivery  is  under  more  complete  control  and  a  greater  choice  of 
methods  is  possible. 

MEASUREMENT  OF  DELIVERY 

The  questions  involved  in  the  desirability  of  measuring  water 
delivered  to  individual  farms  are  not  necessarily  different  for  the 
different  methods  of  delivery.  Measurement  is  probably  less 
usual  in  systems  operating  under  continuous-flow  delivery. 
Some  form  of  measurement  is  needed,  however,  to  equitably 


DELIVERING  IRRIGATION  WATER  113 

divide  the  water  among  the  different  users,  although  records  of 
the  total  amount  used  per  season  may  not  be  kept.  Measure- 
ments of  rate  of  flow  may  be  more  useful  than  measurements  of 
total  quantity  received.  With  rotation  delivery,  the  rotation 
head  used  on  several  farms  may  be  measured  at  one  place  on  the 
lateral  if  only  one  irrigation  head  is  run  on  the  lateral  and  the 
record  completed  by  recording  the  length  of  time  the  head  is 
used  on  each  farm.  If  the  charges  are  to  be  based  on  the  quan- 
tity used,  measurements  at  the  farm  delivery  box  are  preferable. 
With  the  more  irregular  delivery  on  demand,  measurements  of 
rate  of  flow  and  records  of  time  used  on  each  farm  are  needed. 
The  use  of  both  a  uniform  schedule  of  time  per  acre  and  size  of 
irrigation  head  will  give  a  similar  quantity  per  acre  so  that  a  quan- 
tity rate  for  water  approaches  a  uniform  rate  per  acre. 

FORMS  USED  FOR  THE  DELIVERY  OF  WATER 

Nearly  all  canal  systems  find  it  desirable  to  use  printed  forms 
for  obtaining  the  records  of  delivery  of  water.     Some  of  such 


Los  Molinos,  Cal., 191 

CONELAND  WATER  CO., 

Loa  Molinos,  California 

Gentlemen:      On  the day  of. 191 

I  desire  the  water  turned  on  for  my  use  on  Lot Blk 

in  Subdivision  No. - 

(Sign  Here)-- 


Notice  to  Water  Users 

This  application  card  must  be  mailed  or  presented  in  the  Company's 
office  three  days  before  the  date  the  water  is  to  be  used . 

CONELAND  WATER  COMPANY 


FIG.  5. — Form  for  application  for  water  delivery  used  by  Coneland 

Water  Co. 

forms  are  combined  with  the  records  of  measurement  where 
records  of  the  quantity  delivered  are  obtained;  these  combined 
forms  are  discussed  in  Chapter  V.  Some  systems  use  two  forms, 
however,  which  relate  only  to  the  delivery  of  water.  These  are 
the  forms  for  applications  for  water  delivery  and  for  notices  to 
consumers  regarding  the  time  when  delivery  will  be  made. 

Forms  of  Application  for  Water  Delivery. — Blanks  giving  all 
the  data  needed  in  such  applications  requesting  water  delivery 


114 


IRRIGATION  SYSTEMS 


$ 

Riverside 

Deliver  to.           _      _ 

Water  Company 

At  - 

By.                       _        

Above  Water  Ord< 

sred  subject  to  the  Rules  of  the 
Company. 

FIG.  6. — Form  for  application  for  water  delivery  used  by  Riverside 

Water  Co. 


FACE  OF  CARD 


NAME  OF  WATER  USER 


Total 


Acres  In 
Cultiva- 
tion 


Second 

Feet 
Requested 


BACK  OF  CARD 


DEPARTMENT  OF  THE  INTERIOR 

UNITED  STATES  RECLAMATION  SERVICE 

WATER    REQUEST 


7-307b 
January,  1914 


.191. 


U.  S.  Reclamation  Service: 

I  hereby  request  delivery  of  water  at  the  rate. of second-feet 

for days  beginning 191 from  turnout 

No. for lateral  to  irrigate  the  lands 

indicated  on  the  reverse  side  hereof 


Community  Water  Master  or  Canal  rider 


To    Community    Water    Master    or    Canal  Rider.-  In    requesting    crater    jerrice   glre    at     I»a8t    2    days    adrance    notice 

of    your    needs,     usinj    one    of    these    cards  for    etch    run    of    water    desired    or    auj    change    desired    during  a  run.  State 

»ny    requests     for    water     for    other    purpose  than   irrigation.    If    practicable,     report      any     waste   of    water      or    use    of    an. 
excessive    quantity    in    irrigation. 


FIG.  7. — Form  for  application  for  delivery  of  water  to  laterals  of  U.  S. 
Reclamation  Service. 


DELIVERING  IRRIGATION  WATER 


115 


can  be  printed  on  cards  the  size  of  a  postal.  The  water  com- 
pany's address  can  be  printed  on  the  reverse  side  and  the  cards 
distributed  among  the  users.  Such  cards  are  also  a  convenient 
size  for  posting  in  the  boxes  sometimes  attached  to  headgates. 
Where  telephone  requests  are  accepted  a  stamp  indicating  that  a 
request  has  been  received  in  this  manner  can  be  used,  the  form 
being  filled  out  in  the  office  when  received.  The  forms  used 
by  the  Coneland  Water  Co.  and  the  Riverside  Water  Co.  in 


Turlock  Irrigation  District 

APPLICATION  FOR  WATEB  FOR  SEASON  1916 

ROTATION 

40. 

Private  Ditch. 
Drop. 

(Filled  in  by  Ditch  Tender) 

_  .Dist  Lat.  No.    _ 

CROPS    IRRIGATED 

< 

*     " 

5     3 

I  i  1  1  !  §  1  if  §  i 

I      8     •   _8_    I     I      f    St     E     > 

Location  of  L 
_      -Sec 

md_                             _ 

.01            __JS.,    R..       E.    _ 

(Irrigator  Sign  Here) 

Put  remarks  on  other  side 

FIG.  8. — Form  for  seasonal  application  for  water  used  by  Turlock  irrigation 

district. 

California,  Figs.  5  and  6,  are  typical  of  requests  for  individual 
deliveries.  The  form  of  the  U.  S.  Reclamation  Service,  Fig.  7, 
is  useful  for  delivery  to  community  laterals. 

On  some  systems  consumers  are  required  to  make  an  applica- 
tion for  water  at  the  beginning  of  each  season.  This  is  done  in 
some  cases  to  secure  the  areas  to  be  irrigated  which  are  used  in 
planning  rotation  schedules.  The  applications  on  some  systems, 
such  as  commercial  companies,  are  combined  with  an  agreement 
to  pay  the  charges  for  the  season,  such  applications  being  required 


116 


IRRIGATION  SYSTEMS 


before  the  consumer  becomes  eligible  to  receive  service.  Forms 
of  the  first  class  are  illustrated  by  that  of  the  Turlock  irrigation 
district,  Fig.  8. 

In  some  cases  the  consumers  are  required  to  sign  receipts  for 
each  delivery  of  water.  This  will  remove  grounds  for  later  con- 
troversy as  to  the  time  of  deliveries.  Although  the  consumer's 
receipt  has  little  meaning  in  regard  to  the  rate  of  flow,  as  he  is  not 
usually  experienced  in  measurement,  such  receipts  are  useful  in 


Turlock  Irrigation  District 

WATER  RECEIPT  FOB  SEASON  1910 


ROTATION  NO. 


Owner.    Mr. 

(Filled  in  by  Ditch  Tender) 
Private  Ditch 

Drop Dist  Lat.  Xo. 

_HOUR  DAY  MONTK 

Water  Torned.  On ~ 

Water  Turned  OIL — 
Water  Refused— 

CROPS    IRRIGATED 

£       „,       8 

|_J |     8      3      %      %      3      1     52    f. 

Ft. Total  Roars Acre  Feet 

(Trrlgator  Sign  Here) 
Ditch  Tendex.- 

Put  remarks  on  other  side 


FIG.  9. — Form  for  receipt  for  water  delivery  used  by  Turlock  irrigation 

district. 

regular  rotation  schedules  when  those  not  taking  water  for  any 
cause  may  be  required  to  sign  a  refusal  form  showing  the  failure 
to  take  water  to  be  from  their  own  choice.  The  form  of  the  Tur- 
lock irrigation  district,  Fig.  9,  is  bound  in  triplicate  in  small  books, 
each  sheet  having  a  different  color.  These  are  filled  in  by  the 
ditch  rider  and  signed  by  the  user,  one  copy  each  going  to  the  user, 
the  office  and  the  rider.  Blanks  with  receipt  stubs  where  water  is 
delivered  on  demand  on  a  quantity  basis  are  illustrated  by  those  of 
the  Yolo  County  Consolidated  Water  Co.  in  California,  Fig.  10. 


DELIVERING  IRRIGATION  WATER 


117 


Forms  for  Notices  to  Consumers  Regarding  Delivery. — For 

fixed  schedules  under  rotation  delivery  a  notice  is  frequently  sent 
to  the  users  stating  the  time  at  which  water  will  be  delivered. 


No _?__ WOODLAND,  CAL .191 

Received  of  Yolo  County  Consolidated  Water  Company 

From  the -Ditch.- Jeet  of  Water,  ftojn__  o'clock.   3L 

191 to — o'clock M. 191 makings—hours, 

for  which  I  promise  to  pay  the  sum  oL$ with  interestJxo.m 

__L91..ajt_the  rate  of  one  per  cent  per  month  at  Woodland, California 


Received  Payment- 

Yolo  County  Consolidated  Water  Co. 
By___ 


FIG.  10. — Form  for  water  receipt  used  by  Yolo  County  Water  Co. 

This  may  be  done  at  the  beginning  of  the  season  or  for  each 
delivery  during  the  season.  In  some  cases  a  reply  will  be  made  to 
the  application  for  water  under  the  delivery-on-demand  system, 


BACK  OF  CARD 


DEPARTMENT  OF  THE  INTERIOR 

UNITED  STATES  RECLAMATION  SERVICE 

WATER    NOTICE 


.191. 


Dear  Sir: 

Delivery  of  water  to  turnout       from  the lateral 

or  canal  will  be  according  to  the  following  schedule: 

From:  To :  Second-feet  or 

Miner's  inches 


The  above  schedule  supersedes    that  of  any  previous  notice. 


Water  User's  Farm  Unit  or  Holding 

Sec T R 

Sec T R 

Sec. :L R 

—  Sec.__.      __3L_.        ._JEL... 


Canal  Superintendent  or  Rider. 


FIG.  11. — Form  for  notice  of  delivery  of  water  used  by  U.  S.  Reclamation 

Service. 

stating  the  time  water  will  be  furnished.  Post-card  forms  can  be 
used  for  this  purpose.  That  of  the  U.  S.  Reclamation  Service 
(Fig.  11)  is  typical. 

Monthly  notices  may  also  be  sent  to  the  users  giving  the  water 
used  for  the  previous  month  or  to  date  for  the  season.     This  is 


118  IRRIGATION  SYSTEMS 

done  on  those  systems  requiring  monthly  payments.  It  is  also 
frequently  done  on  those  systems  supplying  water  under  an 
agreement  as  to  the  number  of  acre-feet  per  acre  which  will  be 
supplied.  For  such  cases  the  notice  enables  the  user  to  determine 
the  amount  of  water  used  and  that  to  which  he  is  entitled  during 
the  remainder  of  the  season.  Fig.  12  shows  a  form  used  under  the 
gravity  unit  of  the  Minidoka  project. 


DEPARTMENT    OF   THE    INTERIOR 

U.S.  RECLAMATION  SERVICE 
Dear  Sir 

Our  records  show  that  your  assessed  area jis acres 

A  charge  will  be  made  for  water  'delivered  to  above  land  in  excess  of 

1  acre-foot  per  acre  assessedjor- acre-ft. 

Amount  delivered  to  date, acre-ft. 

Balance  available, acre-ft. 

Excess  delivered  to  date^. acre-ft. 

Charge  for  excess  water  delivered  to  date  at  Sc.per  acre  ft., $ 

Remarks:... 


Farm  Unit, Sec fX. ,_R~ 

Farm  Unit, Sec. .^T. ,_#._ 

Project  Manager 


FIG.  12. — Form  for  monthly  notice  of  water  account  used  in  1915  on  gravity 
unit,  Minidoka  project. 

SUMMARY  OF  DELIVERY  METHODS 

There  is  a  marked  tendency  toward  the  adoption  of  some  form 
of  rotation  delivery.  Its  advantages  for  small  farms  or  topo- 
graphic conditions  permitting  the  use  of  large  irrigating  heads 
have  always  been  recognized.  The  use  of  the  method  is  now 
being  extended  for  those  conditions  where  short  periods  and 
relatively  small  irrigation  heads  must  be  used.  With  the  larger 
water  supplies  usually  available  in  the  earlier  systems,  the  use  of 
the  continuous-flow  method  was  natural.  As  water  is  becoming 
more  valuable,  the  expense  of  securing  more  economical  use 
through  more  rigid  operation  methods  is  becoming  warranted. 
The  average  size  of  irrigated  farms  is  also  decreasing  and  land 
is  being  prepared  for  the  use  of  larger  irrigation  heads.  The 
difficulty  of  securing  good  farm  irrigators  and  the  higher  price  of 
farm  labor  are  making  it  necessary  to  secure  methods  of  applying 
water  to  the  land  which  are  more  efficient  from  the  labor  view- 


DELIVERING  IRRIGATION  WATER  119 

point.  For  these  changed  conditions,  the  rotation  method  of 
delivery  is  well  suited. 

The  period  of  change  from  one  method  of  delivery  to  another  is 
always  a  trying  one.  The  irrigators  have  become  accustomed 
to  the  former  practice,  the  farm  ditches  if  built  for  continuous 
flow  have  to  be  enlarged  and  the  method  of  preparing  land  may 
often  need  to  be  changed.  This  involves  considerable  expense 
to  the  farmer,  unless  the  change  is  made  gradually  as  the  crops  in 
each  field  are  changed.  Where  forage  crops  left  for  several  years 
from  each  seeding  are  used,  it  may  take  several  years  before  such 
changes  can  be  economically  completed  on  the  farm.  It  is 
the  expense  of  such  changes,  unless  made  gradually,  which  forms 
the  grounds  for  most  of  the  opposition  to  changes  in  methods. 

During  this  period  of  change  a  mixed  method  of  delivery  may 
be  needed,  giving  varying  sizes  of  irrigation  heads  to  different 
users,  depending  on  their  ability  to  handle  water.  If  the  most 
desirable  size  of  irrigation  head  can  be  determined  in  advance 
of  the  preparation  of  the  lands  and  the  practice  developed  in 
accordance  with  the  use  of  such  heads,  much  later  trouble  and 
expense  may  be  saved.  To  attempt  to  force  changes  in  farm 
practice  from  the  outside  may,  and  sometimes  has,  resulted  in 
developing  an  active  opposition  to  the  change  which  has  retarded 
the  adoption  of  improved  methods  beyond  the  time  when  natural 
conditions,  if  left  undisturbed,  would  have  caused  the  users  to 
adopt  them  of  their  own  accord.  If  the  change  from  continuous 
flow  to  rotation  is  made  after  the  project  is  completely  developed, 
it  may  be  difficult  to  give  satisfactory  service  under  the  mixed 
practice  required  during  the  period  of  change.  If  the  change  can 
be  made  while  the  lands  are  only  partly  developed,  the  excess 
canal  capacity  will  be  of  much  assistance  during  the  period  of 
change. 

CONTROL  OF  LATERALS 

Whether  the  main  canal  organization  should  control  delivery 
to  each  individual  farm  or  only  to  the  groups  of  farms  under  each 
lateral,  as  a  whole,  is  a  subject  on  which  there  has  been  much 
debate.  The  two  general  methods  represent  retailing  and  whole- 
saling of  water;  in  the  latter  case  the  lateral  organization  acts  as 
the  middleman.  As  in  other  types  of  business  some  conditions 
are  favorable  to  each  method. 

It  is  now  generally  conceded  that  it  is  preferable  to  have  the 


120  IRRIGATION  SYSTEMS 

laterals  constructed  by  the  same  organization  which  builds  the 
main  canals.  This  is  particularly  true  on  new  systems  where  the 
settlers  are  secured  gradually,  as  otherwise  the  burden  of  lateral 
construction  on  the  first  settlers  would  be  excessive.  It  is  also 
recognized  that  new  settlers  require  all  of  their  resources  in  pre- 
paring their  lands  for  irrigation  without  giving  time  to  outside 
construction.  Construction  within  a  given  distance  of  each 
farm  is  also  the  only  basis  on  which  the  total  cost  is  made  uni- 
form as  the  cost  of  lateral  construction  will  vary  with  the  topo- 
graphic conditions  in  different  parts  of  the  system. 

The  operation  of  laterals  by  some  form  of  cooperative  associa- 
tion is  an  outgrowth  of  the  earlier  and  smaller  system  both  built 
and  operated  by  such  organizations.  On  the  larger  systems  the 
personal  acquaintance  and  unity  of  purpose  which  made  such 
smaller  systems  successful  is  more  difficult  to  secure.  The  coop- 
erative lateral  associations  are  most  successful  where  the  condi- 
tions are  similar  to  those  of  the  earlier  developments,  such  as 
those  cases  where  all  the  lands  are  settled  at  the  time  of  construc- 
tion, where  the  owners  are  bound  together  by  other  forces  such  as 
necessity,  race  or  religion,  or  are  accustomed  to  cooperation  in 
other  lines.  It  is  not  successful  where  the  settlers  are  secured 
from  scattered  sources  and  have  little  or  no  irrigation  experience. 

The  principal  weakness  of  such  lateral  associations  is  the  lack 
of  a  definite  organization.  It  is  necessary  to  have  such  organiza- 
tions both  to  deal  with  the  main  canal  organization  and  to  com- 
pel compliance  with  the  lateral  regulations.  Where  the  area 
covered  by  a  lateral  is  too  small  to  require  the  continuous  time 
of  a  ditch  rider,  there  is  liable  to  be  little  direction  in  the  distribu- 
tion of  water.  This  may  result  in  the  lower  owners  having  to 
act  as  unofficial  ditch  riders  in  order  to  get  water  through  to  their 
lands.  This  causes  loss  of  time  on  their  part  and  more  or  less 
continual  friction  between  the  users,  unless  the  lateral  capacity 
and  water  supply  are  in  excess  of  their  needs.  On  larger  laterals 
the  organization  may  be  similar  to  a  mutual  or  stock  company 
which  is  incorporated  and  with  more  definite  regulations  and 
methods  of  assessment. 

The  lateral  association  may  have  trouble  with  both  operation 
and  maintenance.  Those  located  near  the  upper  end  may 
object  to  doing  their  full  share  of  the  maintenance.  Those  at 
the  lower  end  can  secure  water  only  when  the  whole  lateral  is  in 
condition  for  operation,  and  it  sometimes  happens  that  such 


DELIVERING  IRRIGATION  WATER  121 

owners  have  to  do  more  than  their  proportion  of  such  work. 
This  has  been  partially  remedied  in  some  States  by  the  enactment 
of  laws  by  which  one  owner  on  a  lateral  can,  on  the  failure  of  the 
others  to  do  their  part,  do  the  work  and  collect  the  cost  from  the 
others.  Maintenance  of  canals  is  more  easily  secured  than 
maintenance  of  structures,  as  canal  cleaning  can  be  done  by  the 
owners  without  cash  outlay;  structure  materials  require  cash 
assessments.  The  enforcement  by  the  main-canal  organization 
of  a  rule  that  no  water  will  be  delivered  to  any  lateral  until  it  is 
in  condition  for  delivering  to  all  owners  will  also  assist  in  pro- 
curing proper  maintenance. 

The  desirability  of  such  lateral  associations  from  the  point  of 
view  of -the  main-canal  operator  depends  on  the  method  of  charg- 
ing for  water,  the  extent  of  responsibility  of  the  main-canal 
system  for  individual  delivery  and  the  size  of  the  lateral.  The 
detail  records  are  materially  reduced  where  the  main-canal  sys- 
tem delivers  to  a  lateral  as  a  unit  without  records  or  collection 
from  the  individuals.  Where  rotation  delivery  is  used,  the  area 
under  the  laterals  may  be  large  enough  to  use  a  given  number  of 
delivery  heads  continuously,  giving  continuous  delivery  to  the 
lateral  and  simplifying  the  main-canal  operation.  Delivery  on 
demand  is  more  difficult  to  adjust.  If  water  is  paid  for  on  an 
acre-foot  basis,  unless  sold  at  wholesale  to  the  lateral,  it  is  essen- 
tial that  the  delivery  to  each  farm  be  under  the  control  of  the 
main-canal  organization.  Where  the  operation  charges  are  on  a 
flat  acreage  basis,  this  is  not  necessary.  On  some  systems  there 
is  a  preference  for  the  employment  of  ditch  riders  who  do  not 
have  any  land  or  other  direct  interests  under  their  beats.  This 
can  be  more  easily  secured  where  the  main  canal  controls  the 
complete  delivery  as  the  officers  of  the  lateral  associations  are 
more  usually  those  securing  water  from  the  lateral. 

On  systems  where  it  is  contemplated  that  the  canal  system 
will  be  turned  over  to  the  land  owners  on  the  completion  of  the 
payments  for  construction  cost  it  has  been  argued  in  some  cases 
that  by  first  turning  the  laterals  over  to  the  users  under  them, 
they  would  gain  experience  which  will  later  enable  them  to 
handle  the  entire  system  more  efficiently.  On  a  few  of  the  sys- 
tems of  the  U.  S.  Reclamation  Service  such  attempts  have  been 
made  but  the  land  owners  have  not  generally  cared  to  undertake 
such  partial  control.  This  method  might  be  desirable  if  it  is 
intended  that  each  land  owner  shall  share  in  the  operation  of  the 


122  IRRIGATION  SYSTEMS 

whole  system.  On  large  systems  this  is  not  desirable,  as  the 
operation  should  be  turned  over  to  elected  officials  who  are  given 
full  responsibility  and  power.  The  individual  water  user  should 
qualify  himself  to  judge  of.  the  efficiency  and  economy  of  the 
results  secured  but  to  participate  only  through  elected  or  selected 
officers. 

Examples  of  Practice. — On  the  gravity  unit  of  the  Minidoka 
project  the  laterals  were  built  and  operated  by  lateral  associa- 
tions. The  results  were  not  satisfactory  and  practically  all  of  the 
laterals  were  taken  over  and  operated  by  the  Reclamation 
Service.  On  the  pumping  unit  of  the  same  project  all  laterals 
were  built  and  are  operated  by  the  Reclamation  Service.  At 
the  time  of  construction  the  Modesto  and  Turlock  irrigation 
districts  did  not  build  the  laterals.  At  present  a  large  part  of 
these  laterals  have  been  taken  over  by  the  district  organizations 
in  order  to  be  able  to  give  better  service.  On  the  adjacent 
South  San  Joaquin  district,  built  after  these  districts  had  been 
in  operation  for  some  years,  laterals  were  built  by  the  district 
to  deliver  water  to  each  40  acres.  A  number  of  cases  have  come 
before  the  California  Railroad  Commission  in  which  land  owners 
under  laterals  have  desired  to  have  the  main-canal  system  take 
over  the  operation  and  maintenance  of  the  laterals.  Where  the 
lateral  is  not  owned  by  the  main-canal  system  the  Commission 
has  held  that  it  has  no  authority  to  compel  them  to  operate  it, 
although  in  some  cases,  such  as  those  under  the  Fresno  Canal 
and  Irrigation  Co.'s  system,  the  canal  company  had  reserved  the 
right  to  take  over  the  laterals  at  their  own  option.  The  Com- 
mission has,  however,  approved  agreements  whereby  by  the 
payment  of  a  rate  in  excess  of  that  allowed  for  delivery  to  the 
lateral  only,  the  main-canal  system  has  consented  to  take  over 
the  laterals.  Such  additional  rates  are  based  on  the  estimated 
cost  of  the  additional  duties  placed  on  the  main-canal  system. 

In  decision  No.  1265  of  the  California  Railroad  Commission, 
involving  the  Soledad  Land  and  Water  Co.,  it  is  stated: 

"Experience  has  shown  that  it  is  to  the  interest  of  both  the  con- 
sumer and  the  company  that  the  operation  and  maintenance  of  all  the 
distributaries  to  the  point  of  delivery  of  water  to  individual  consumers 
shall  be  conducted  by  the  company.  Where  the  company  controls 
and  operates  the  ditches  and  laterals  under  uniform  rules,  fair  and 
equitable  distribution  of  the  water  is  possible  and  the  system  can  be 
maintained  in  good  order  and  repair.  On  the  other  hand,  where  con- 


DELIVERING  IRRIGATION  WATER  123 

sumers  are  compelled  to  care  for  the  ditches  and  laterals  serious  evils 
result.  Where  several  consumers  are  located  on  a  lateral  and  they 
do  not  require  water  at  the  same  time,  a  man  who  first  needs  water  is 
compelled  to  clear  and  clean  the  lateral  or  ditch  from  the  plant  to  his 
land  at  his  own  expense.  Thereafter,  the  other  consumers  on  this 
ditch  or  lateral  can,  with  slight  expense  to  themselves,  take  advantage 
of  their  neighbor's  expenditure.  Controversy  will  also  arise  over  dis- 
tribution of  the  water.  All  these  difficulties  can  be  obviated  only  by 
organization  of  the  consumers,  which  is  difficult  and  often  comparatively 
expensive  and  unsatisfactory  in  operation." 

The  method  used  under  the  Amity  canal  in  Colorado  is  typical 
of  that  of  many  of  the  older  companies.  The  laterals  are  run 
along  ridges  and  serve  distinct  areas  averaging  over  2,000  acres 
each.  The  Amity  canal  constructed  the  laterals  and  turned 
them  over  to  the  lateral  company  as  soon  as  there  were  three 
users  under  the  lateral,  the  title  being  retained  by  the  Amity 
canal.  The  lateral  company  cannot  sell  or  dispose  of  the  lateral, 
but  is  responsible  for  its  maintenance  and  operation.  Stock  in 
the  lateral  was  issued  to  the  water-right  holders  and  was  appur- 
tenant to  certain  described  land,  the  stock  for  any  unsold  water 
rights  being  retained  by  the  Amity  canal. 

These  somewhat  conflicting  instances  serve  to  show  that 
practice  is  not  uniform  in  regard  to  such  lateral  associations. 
In  general  it  can  be  said  that  they  are  not  desirable  unless  the 
lateral  association  has  a  definite  organization  and  that  such 
organizations  are  economical  only  where  the  area  under  the 
lateral  is  relatively  large.  They  do  not  reduce  the  total  cost  of 
service  to  the  individual  but  divide  it  into  two  parts  whose 
total  more  frequently  exceeds  the  cost  of  complete  service  by  one 
organization. 

REFERENCES  FOR  CHAPTER  IV 

ADAMS,  F. — Delivery  of  Water  to  Irrigators,  1910,  Bulletin  229,  Office  of 

Experiment  Stations,  U.  S.  Department  of  Agriculture. 
Continuous   versus    Rotation    Delivery,    1912,    Report   of   Conference   of 

Operating  Engineers,  Bozeman,  Mont. 

HANNA,  F.  W. — Irrigation  Management,  Engineering  News,  Feb.  12,  1912. 
DARLINGTON,  E.  B. — Methods  of  Water  Delivery,  1913,  Second  Conference 

of  Operating  Engineers,  Boise,  Idaho. 
Rotation  or  Continuous  Delivery  of  Water  for  Irrigation  Purposes,  Series 

of  Discussions,  1913  Conference  of  Operating  Engineers,  Great  Falls, 

Mont. 
STOCKTON,   R.  S. — Management  of  Irrigation  Systems,   Engineering  and 

Contracting,  Jan.  28,  1914. 


124  IRRIGATION  SYSTEMS 

PYLE,    F.   D. — Rotation  versus   Continuous   Flow,    Reclamation   Record, 

January,  1916. 
Lateral  Ditch  Companies,  1904,  p.  615,  Bulletin  158,  Office  of  Experiment 

Stations,  U.  S.  Department  of  Agriculture. 

JUMP,  C.  M. — Operation  and  Maintenance  of  Canals,  Laterals  and  Dis- 
tributaries by  the  Settlers,   1909  Conference  of  Operating  Engineers, 

Powell,  Wyo. 
REED,  M.  E. — Association  of  Water  Users  for  Operation  and  Maintenance  of 

Distributing  Canals,  1909  Conference  of  Operating  Engineers,  Powell, 

Wyo. 
Operation  by  United  States  of   Main  Canal,  Laterals  and  Distribution 

Systems,  Series  of  Discussions,  1913  Conference  of  Operating  Engineers, 

Great  Falls,  Mont. 
Various   Decisions  of   California  Railroad   Commission  in   Opinions   and 

Orders,  Vols.  1  to  9. 


CHAPTER  V 
MEASUREMENT  OF  IRRIGATION  WATER 

Hydrographic  measurements  in  connection  with  the  operation 
of  irrigation  systems  have  received  much  attention  in  the  last 
few  years.  On  many  systems  similar  arguments  are  being  made 
in  regard  to  the  desirability  or  need  of  measuring  the  quantities 
of  water  delivered  to  individual  consumers  which  have  been 
made  on  municipal  water-supply  systems.  The  same  obstacle 
as  to  the  cost  of  such  measurement  or  metering  is  encountered 
with  the  additional  difficulty  for"  irrigation  systems  that,  even 
if  the  desirability  is  admitted  and  the  funds  available  for  installa- 
tion, many  questions  still  remain  to  be  solved  regarding  the 
type  of  measuring  device  to  be  used  and  the  accuracy  of  the 
results  which  will  be  secured.  In  water-works  practice  a  large 
amount  of  experience  with  meters  is  available  from  which  the 
results  of  metering  any  system  can  be  largely  determined  in 
advance;  with  irrigation  practice  the  conditions  on  different 
systems  vary  more  widely  and  the  experience  of  others  cannot  be 
as  directly  applied. 

Irrigation  hydrography,  or  hydrometry  as  it  is  sometimes  and 
perhaps  more  correctly  called,  can  be  divided  into  two  main 
divisions.  Certain  measurements  of  the  flow  in  the  canals  are 
needed  in  the  operation  of  the  system.  These  are  required  by 
the  operating  organization  for  its  own  use  in  order  to  handle  the 
division  of  water  between  laterals,  etc.,  and  do  not  directly 
concern  the  charges  to  consumers  individually.  The  second 
division  consists  of  the  measurement  of  the  water  delivered  to 
individual  consumers.  Many  canal  systems  carry  out  more  or 
less  general  hydrography  without  making  measurements  of 
individual  deliveries.  Many  bulletins  and  books  are  available 
covering  the  measurement  of  water  both  generally  and  specific- 
ally for  different  conditions,  references  to  a  number  of  which  are 
given  at  the  end  of  the  chapter.  Applications  to  irrigation  prac- 
tice are  discussed  in  this  chapter,  avoiding  as  much  as  possible 
general  methods  or  principles,  a  knowledge  of  which  is  assumed. 

125 


126  IRRIGATION  SYSTEMS 

The  use  of  measurement  of  both  of  the  above  types  is  increas- 
ing. This  is  the  natural  result  of  the  increasing  value  of  water. 
It  is  only  when  the  value  of  water  saved  warrants  the  cost  of 
closer  control  of  delivery,  including  measurement,  or  where 
the  actual  damage  from  overuse,  such  as  from  water-logging 
occurs,  that  measurement  of  individual  deliveries  has  been 
generally  adopted.  As  these  conditions  are  becoming  felt  on 
an  increasing  proportion  of  irrigation  systems,  the  use  of  measured 
delivery  is  naturally  increasing.  Efforts  to  introduce  such 
measured  delivery  where  conditions  do  not  make  it  actually 
of  definite  or  immediate  advantage  to  the  users  have  generally 
been  unsuccessful. 

Where  the  services  of  hydrographers  are  available  it  is  generally 
found  that  they  can  be  used  to  advantage  on  more  or  less  special 
work  such  as  checking  measuring  devices,  special  gagings  in 
cases  of  disputes,  canal-seepage  tests  and  observations  in  connec- 
tion with  drainage  such  as  water-table  fluctuations.  While  at 
present  separate  hydrographers  are  not  employed  on  the  majority 
of  systems  their  use  is  increasing.  In  the  first  years  of  operation 
the  smaller  area  irrigated  can  be  supplied  without  the  need  of 
close  control  of  the  flow  in  the  canals.  In  later  years  the  problems 
of  the  division  of  water  are  more  complex  and  the  need  for  hydro- 
graphic  work  is  greater.  On  systems  of  over  50,000  acres  a 
hydrographer  can  be  used  to  advantage  if  the  water  supply  is 
limited.  On  smaller  systems  part  time  of  an  instrumentman 
may  be  sufficient  to  handle  the  necessary  gagings. 

Hydrographic  work  on  irrigation  systems  requires  an  under- 
standing of  hydraulic  principles.  This  should  include  not  only 
a  knowledge  of  the  conditions  necessary  to  insure  accuracy  in 
the  use  of  different  methods  of  measurement,  but  also  an  appre- 
ciation of  the  effects  of  variations  from  such  conditions.  It  is 
often  necessary  to  use  devices  under  unfavorable  conditions  of 
velocity  of  approach  or  submergence  and  an  understanding  of 
how  far  such  conditions  can  be  permitted  to  go  before  corrections 
are  needed  or  before  the  certainty  of  the  entire  measurement  is 
materially  affected  is  as  essential  as  a  knowledge  of  the  theoretical 
conditions  desired.  Hydrographic  positions  offer  an  excellent 
opportunity  to  obtain  operation  and  maintenance  experience  as 
one  is  brought  into  contact  with  all  branches  of  the  work.  The 
salaries  paid  usually  vary  from  $75  to  $100  per  month  for  inex- 
perienced men  to  as  high  as  $125  to  $150  per  month  for  ex- 


MEASUREMENT  OF  IRRIGATION  WATER       127 

perienced  men  in  charge  of  such  work  on  large  systems.  Hydro- 
graphers  may  be  employed  only  during  the  summer  season  or 
used  on  the  other  work  during  the  winter.  On  large  systems  a 
portion  of  the  hydrographic  organization  may  be  used  on 
computations  throughout  the  year. 

CANAL  HYDROGRAPHY 

The  use  of  rating  stations  on  canals  varies  from  no  measure- 
ments to  careful  ratings  of  diversions  from  the  stream  and  sub- 
divisions between  laterals.  It  is  usual  to  maintain  a  rating 
station  at  the  head  of  the  diversion  canal.  On  many  streams 
such  stations  are  required  by  law  for  use  in  connection  with 
the  administration  of  adjudicated  water  rights.  Where  the 
purpose  of  such  a  station  is  merely  to  satisfy  such  legal  require- 
ments, neither  the  location  or  equipment  of  the  rating  station 
are  usually  as  carefully  selected  or  maintained  as  for  stations  the 
results  of  which  are  directly  used  in  the  operation  of  the  canal 
system.  Rating  stations  are  needed  to  control  the  division  of 
water  to  main  laterals  within  the  system.  The  extent  to  which 
such  stations  are  used  on  the  smaller  laterals  depends  on  local 
conditions.  If  the  available  supply  is  to  be  divided  to  the 
different  laterals  closely  in  proportion  to  the  requirements  of 
contracts  or  the  acreage  served,  such  measurements  will  be 
needed.  Where  the  form  of  lateral  headgate  is  such  that  it 
can  be  used  as  a  more  or  less  satisfactory  measuring  or  dividing 
device,  a  division  on  such  basis  is  usual.  Some  systems  main- 
tain rating  stations  at  the  heads  of  laterals  although  this  is 
restricted  to  the  larger  laterals  in  most  cases. 

The  use  of  measuring  devices  requiring  a  free  fall  for  measure- 
ment is  generally  limited  by  practical  considerations  to  quan- 
tities of  100  second-feet  or  less.  Approximate  measurements 
may  be  secured  for  larger  quantities  by  headgates  or  check  gates 
used  as  orifices,  but  the  number  of  openings  in  use  or  uncertainty 
as  to  the  correct  value  of  the  coefficient  renders  such  results 
uncertain.  Some  form  of  drops  such  as  the  notch  type  may  be 
used  for  measurement  of  larger  quantities.  Weirs  for  larger 
flows  require  conditions  not  usually  obtainable  on  canals.  With 
large  checks  or  drops  the  uncertainty  as  to  the  proper  formula 
or  coefficients  makes  it  practically  necessary  to  rate  each  such 
structure  in  use,  the  structure  serving  as  a  control  for  the  rating 


128  IRRIGATION  SYSTEMS 

rather  than  as  a  measuring  device  itself.  For  fixed  structures 
such  as  notch  drops,  the  rating  should  be  permanent;  for  checks 
the  variations  in  opening  may  affect  the  velocity  of  approach 
conditions  and  consequently  the  rating. 

Records  are  also  kept  of  the  waste  from  the  canals  in  their 
regulation.  Such  waste  may  occur  at  spillways  placed  just 
below  the  headgate  and  used  to  regulate  the  amount  diverted. 
For  such  cases  the  main  rating  station  may  be  placed  below  the 
spillway,  giving  the  amount  taken  into  the  canal  system  directly. 
Other  waste  along  the  diversion  canal  or  at  the  ends  of  laterals 
may  be  measured.  The  sum  of  such  discharges  for  the  season 
represents  the  operation  waste  of  the  system  and  is  frequently 
expressed  as  a  percentage  of  the  gross  duty.  On  closely  regulated 
systems  it  may  be  quite  small;  for  systems  of  ample  water  supply 
and  wasteway  facilities  it  may  amount  to  20  per  cent,  or  more  of 
the  amount  diverted. 

Requirements  of  Canal  Rating  Stations. — A  canal  rating  sta- 
tion depends  on  the  determination  of  the  relation  between  depth 
of  flow  and  discharge.  To  be  satisfactory  such  relationship 
must  be  fixed  or  permanent.  Where  the  relation  of  depth  of 
flow  and  discharge  is  not  fixed,  methods  of  correction  must  be 
used  which  increase  the  expense  of  operation  of  a  station  and 
reduce  the  accuracy  obtained.  Canal  ratings  are  expressed  as 
the  relation  between  the  gage  height  and  the  discharge.  The 
discharge  at  any  section  is  the  product  of  the  area  times  the  mean 
velocity.  For  a  given  cross-section  which  is  not  subject  to  change 
the  area  is  proportional  to  the  depth  of  flow  which  is  represented 
by  the  gage  height.  For  a  given  length  of  canal  in  which  both 
the  character  of  the  wetted  perimeter  or  coefficient  of  roughness 
and  the  slope  do  not  change,  the  relation  between  the  mean 
velocity  and  the  gage  height  is  fixed.  In  order  that  the  rating 
of  any  section  may  be  constant  or  fixed  it  is  therefore  neces- 
sary that  the  cross-sectional  area,  the  slope  and  the  coefficient 
of  roughness  remain  constant.  For  such  conditions  the  actual 
determination  of  the  discharge  at  a  few  gage  heights  distributed 
over  the  variations  in  depth  which  occur  can  be  used  as  the  basis 
for  determining  the  discharge  at  intermediate  stages. 

In  many  rating  stations  on  rivers  the  conditions  are  such  that 
the  ratings  remain  fairly  constant.  In  canal  rating  stations 
such  constancy  of  rating  is  more  difficult  to  secure.  The  condi- 
tions of  use,  silting,  or  the  growth  of  vegetation  may  affect  the 


MEASUREMENT  OF  IRRIGATION  WATER       129 

rating.  The  control  of  the  area  of  the  cross-section  at  the  point 
at  which  the  gage  is  located  can  be  secured  by  the  use  of  rating 
flumes  or  similar  means.  The  effect  of  changing  canal  slope  can 
be  overcome  in  some  cases  by  the  location  of  rating  stations 
closely  above  control  structures  of  fixed  openings.  The  effect 
of  changes  in  the  coefficient  of  roughness  can  also  be  overcome 
by  locating  the  station  above  and  close  to  control  stations. 
Where  such  controls  can  be  secured  they  furnish  the  best  loca- 
tions for  stations. 

To  give  good  results  the  control  has  to  be  free  from  the  effects 
of  slope  in  the  canal  or  have  a  constant  relation  to  such  changes. 
This  is  secured  only  where  the  control  itself  does  not  change;  a 
check  having  variable  openings  will  not  control  a  canal  rating. 
To  be  unaffected  by  changes  in  the  canal  below,  free  or  nearly 
free  fall  at  the  control  is  required.  Such  stations  may  be  ob- 
tainable on  delivery  canals ;  it  is  more  difficult  to  secure  them  on 
laterals  on  which  the  flow  is  checked  for  delivery.  Ratings  near 
the  heads  of  long  flumes  or  lined  sections  which  are  not  subject 
to  silt  or  aquatic  growth  may  not  be  subject  to  change.  A  rating 
flume  of  short  length  controls  only  the  cross-section  area  and  will 
not  have  a  constant  rating  unless  the  other  requirements  are 
satisfied  by  the  conditions  in  the  adjacent  canal.  Rating  sta- 
tions operated  under  such  control  differ  from  those  controlled  by 
the  flow  in  canals  under  the  influence  of  the  slope.  Such  controls 
are  similar  in  nature  to  weirs.  With  a  weir  the  rating  curve  has 
been  reduced  to  a  mathematical  formula;  with  the  usual  forms 
of  drops  or  other  control  it  is  necessary  to  make  a  field  rating,  the 
rating  depending  upon  conditions  of  free  fall  rather  than  of 
slope.  Such  free-fall  conditions  are  not  affected  by  changes  in 
the  adjacent  canal  unless  such  changes  submerge  the  control. 

Such  rating  stations  and  rating  curves  are  the  basis  of  nearly 
all  stream-gaging  stations.  On  some  streams  changes  in  the 
channels  affect  the  rating  curves  but  on  the  whole  such  diffi- 
culties are  much  less  in  rivers  than  in  canals. 

Equipment  of  Gaging  Stations. — Actual  gagings  can  be  made 
at  any  uniform  and  permanent  cross-section  of  the  canal.  To 
secure  such  permanence  of  cross-section  a  short  length  of  canal 
may  be  lined.  It  is  preferable  that  the  section  of  such  rating 
station  be  similar  to  the  average  of  the  adjacent  canal.  The 
floor  should  be  set  slightly  above  the  subgrade  of  the  adjacent 
canal  in  order  to  reduce  the  tendency  toward  silting.  If  such 


130  IRRIGATION  SYSTEMS 

rating  flumes  are  used  there  is  little  disturbance  of  the  lines  of 
flow  in  the  canal  and  a  shorter  length  of  lining  will  be  needed. 
Lengths  equal  to  the  bottom  width  for  canals  up  to  20  or  30  feet 
bottom  width  are  representative  of  good  practice;  a  length  of 
20  feet  should  be  sufficient  for  larger  canals  of  relatively  uniform 
cross-section.  Such  stations  should  be  located  in  lengths  of 
straight  canal  to  avoid  the  disturbance  of  flow  due  to  curves. 
In  many  cases  rating  sections  of  short  lengths  of  vertical  sided 
flumes  have  been  built  in  canals.  These  necessarily  are  subject 
to  changes  in  the  lines  of  flow  at  the  inlet  and  outlet  and  are  not 
as  desirable  on  large  canals  or  with  higher  velocities.  Where 
relatively  long  flumes  or  lined  sections  are  used  the  rating  station 
can  be  placed  at  any  point  where  the  alignment  is  satisfactory. 

The  actual  gagings  are  usually  made  from  some  form  of  bridge. 
The  use  of  permanent  bridges  on  which  the  spacing  of  the  ve- 
locity verticals  can  be  marked  enables  the  gagings  to  be  more 
quickly  and  conveniently  made.  For  spans  up  to  40  feet  poles 
having  a  2-inch  X  12-inch  foot  plank  fastened  to  the  upper  side 
may  be  used.  For  longer  spans  light  cable  suspension  foot 
bridges  are  satisfactory.  These  can  be  built  relatively  cheaply 
and  do  not  cause  any  obstruction  to  the  canal  flow.  For  the 
widths  of  spans  found  in  canal  practice  such  suspension  foot 
bridges  are  preferable  to  the  cable  and  car  stations  used  on  rivers. 
Highway  bridges  are  frequently  used.  This  is  satisfactory  if  the 
other  conditions  for  gaging  are  favorable.  The  availability  of 
such  a  bridge,  however,  is  often  used  to  fix  the  location  of  a 
station  where  the  hydraulic  conditions  are  not  the  best.  If  there 
are  piers  in  the  canal,  an  extension  with  a  foot  plank  can  be 
built  on  the  upstream  side  so  that  the  meter  can  be  held  far 
enough  upstream  from  the  piers  to  be  free  from  their  influence. 
Wading  measurements  may  be  made  for  depths  of  less  than  3 
feet  and  for  the  slower  velocities.  These  are  not  desirable  for 
permanent  gaging  stations  as  the  cost  of  the  bridge  will  be  repaid 
by  the  saving  in  the  time  required  for  gaging.  The  resulting 
accuracy  may  also  be  somewhat  more  uncertain  with  wading 
measurements.  At  a  well-equipped  station  a  hydrographer  is 
usually  able  to  set  up  his  meter,  read  two  points  in  8  to  12  verticals, 
secure  gage  heights  and  other  notes  for  a  gaging,  and  be  ready  to 
leave  in  about  1  hour's  time.  The  time  spent  in  going  from  one 
station  to  another  is  often  more  important  than  the  time  spent 
in  actual  gaging. 


MEASUREMENT  OF  IRRIGATION  WATER       131 

Rating  Stations  Not  Subject  to  Control.— The  method  of 
handling  canal  rating  stations  subject  to  the  influence  of  checks 
and  of  aquatic  growth,  developed  by  Mr.  J.  S.  Longwell  on  the 
Minidoka  project,  while  somewhat  cumbersome  to  apply,  will 
enable  fairly  satisfactory  results  to  be  obtained  in  sections 
affected  by  both  of  the  above  influences.  On  portions  of  this 
project  there  is  little  fall  to  the  land  away  from  the  canals  so  that 
checking  is  required  for  delivery.  Also,  aquatic  growths  materi- 
ally affect  the  value  of  n  during  the  season.  Such  changes  in 
the  control  of  gaging  stations  make  it  necessary  to  use  correc- 
tion methods.  In  this  method  the  rating  stations  are  located 
in  uniform  sections  of  the  canal  and  as  far  from  the  influence  of 
checks  as  possible.  In  addition  to  the  gage  at  the  rating  station, 
a  second  gage  is  also  used  located  downstream  but  within  the 
same  checking  influence.  The  two  gages  are  set  with  their 
zeros  aty  the  same  elevation  relative  to  the  subgrade  of  the 
canal.  j/The  mean  of  the  two  gages  at  any  time  will  then  give 
the  mean  depth  between  the  gages  and  is  used  for  the  hydraulic 
functions  at  that  time.  The  distance  between  the  gages  is  also 
determined. 

A  standard  canal  cross-section  is  determined,  which  is  used  as 
the  mean  for  the  length  of  canal  between  the  gages.  This  can 
be  determined  from  a  number  of  actual  cross-sections.  If  the 
canal  is  sufficiently  uniform  in  section  to  be  suited  to  use  for 
canal  rating,  the  cross-section  at  the  actual  gaging  station  can 
be  used.  From  this  mean  cross-section  the  wetted  perimeter, 
area  and  hydraulic  radius  for  different  depth  are  determined. 
From  these  properties  and  the  discharge  and  water  surface  slope 
as  measured  at  each  gaging,  the  value  of  n  in  Kutter's  formula 
can  be  computed  for  each  discharge  measurement.  The  value 
of  n  will  usually  vary  during  the  season  due  to  the  effect  of 
aquatic  growths.  What  is  called  the  normal  value  of  n  is  as- 
sumed, being  usually  the  value  found  in  the  early  part  of  the 
season  when  the  canal  section  is  relatively  free  from  growth. 
For  this  normal  value  of  n  a  rating  curve  is  computed  for  dif- 
ferent depths  using  the  slope  of  the  water  surface  as  observed 
during  the  period  of  minimum  checking.  This  normal  rating 
curve  is  plotted  in  the  usual  form,  curves  for  the  area  of  cross- 
section,  hydraulic  radius  and  mean  velocity  also  being  plotted 
on  the  same  sheet  as  shown  in  Fig.  13. 

As  each  gaging  is  made  during  the  season,  the  result  is  plotted 


132 


IRRIGATION  SYSTEMS 


on  the  normal  rating  curve  sheet.  The  vertical  distance  of  the 
plotting  from  the  normal  rating  curve  is  used  to  give  the  gage- 
height  correction.  Such  corrections  depend  on  both  canal 
checking  and  the  value  of  n.  »/If  the  value  of  n  is  constant,  the 


Seasonal  Correction  Curves 
June  July        /\  August         September         October 


150  200  250  300  350 

Discharge  in  Second  Feet 

FIG.  13. — Curves  used  for  rating  stations  not  subject  to  control. 

correction  will  depend  on  the  conditions  of  checking.  The  effect 
of  checking  shows  in  the  change  in  the  slope  of  the  canal-water 
surface  which  is  determined  from  the  readings  of  the  two  gages. 
For  any  value  of  n,  the  fall  between  the  gages  and  the  correction 


MEASUREMENT  OF  IRRIGATION  WATER       133 

for  different  amounts  of  checking,  will,  if  plotted,  fall  on  a  smooth 
curve.  Such  a  curve  for  the  value  of  n  found  in  the  earlier  season 
can  be  determined,  as  at  that  time  the  value  of  n  varies  more 
slowly  and  the  corrections  are  mainly  due  to  the  effect  of  check- 
ing. Gagings  at  weekly  periods  are  required  to  give  close  results 
under  such  conditions.  For  each  gaging  the  value  of  n  is  com- 
puted. The  fall  and  correction  for  each  gaging  are  plotted  on 
the  general  fall  and  correction  curve.  A  series  of  fall-correc- 
tion curves,  generally  parallel  in  direction,  are  thus  developed 
for  the  various  values  of  n.  The  corrections  for  the  daily  gage 
readings  are  secured  by  using  the  fall-correction  curve  for  the 
value  of  n  found  at  the  last  gaging,  entering  with  the  observed 
fall  for  the  daily  gage  readings  and  taking  off  the  corresponding 
correction.  This  correction  is  then  applied  to  the  mean  of  the 
two  gage  readings  for  the  day,  the  corrected  mean  gage  being 
applied  to  the  normal  canal  rating  to  give  the  corrected  dis- 
charge. As  an  additional  check,  the  daily  corrections  are  plotted 
on  a  time  curve  for  the  operation  season.  The  corrections  due 
to  checking  are  greatest  at  the  beginning  and  end  of  the  season 
when  small  discharges  are  checked  back  for  delivery.  At  the 
height  of  the  season  the  full  slope  of  the  canal  will  usually  be 
required  to  carry  the  water  needed.  Corrections  due  to  changes 
in  the  value  of  n  will  depend  on  the  growth  of  moss  or  other 
aquatic  vegetation.  Such  corrections  may  increase  until  it  is 
necessary  to  cut  the  growth  in  order  to  be  able  to  carry  the  de- 
sired capacity.  Following  such  cuttings  the  value  of  n  may  be 
as  low  as  the  normal  value  and  the  correction  correspondingly 
small.  Using  this  method  about  20  rating  stations  can  be 
handled  by  one  field  man.  This  includes  weekly  gagings  and 
the  keeping  up  to  date  of  the  records  of  such  stations. 

Current-meter  measurements  have  been  used  in  the  delivery 
of  water  from  the  main-canal  system  in  the  Imperial  Valley. 
Owing  to  the  large  amount  of  silt  carried  and  the  resulting  rapid 
changes  in^conditions  at  orifices  or  other  devices  no  other  method 
has  been  found  to  be  satisfactory  for  large  quantities.  Daily 
gagings  are  made  on  deliveries  to  some  canals  such  frequency  of 
rating  doing  away  with  the  need  of  special  correction  methods 
for  rating  curves.  A  special  current-meter  rating  station  is  used 
as  it  has  been  found  that  the  wear  on  the  bearings  of  the  meter, 
due  to  the  silt,  make  frequent  meter  ratings  desirable. 


134  f     IRRIGATION  SYSTEMS 

METHODS  OF  CANAL  MEASUREMENT 

The  methods  of  use  of  current  meters  in  irrigation  canals  are 
similar  to  those  used  in  rivers  or  other  channels.  These  methods 
are  fairly  well  standardized  and  are  discussed  in  a  number  of 
bulletins  and  books.  The  greater  uniformity  in  cross-section 
and  in  character  of  wetted  perimeter  usual  in  irrigation  canals 
gives  a  somewhat  more  uniform  velocity  distribution  than  is 
found  in  many  natural  channels  so  that  more  accurate  and  con- 
sistent results  are  to  be  expected  in  canal  gagings.  These  condi- 
tions also  enable  some  slight  modifications  in  the  methods  used 
in  general  channels  to  be  made.  Available  comparisons  of  the 
accuracy  of  different  methods  of  canal  gaging  with  current  meters 
have  been  made  only  on  the  basis  of  the  consistency  of  such 
results  as  with  larger  canals,  other  comparative  methods  at 
practicable  cost  are  not  feasible.  From  a  large  number  of  carefully 
detailed  gagings  of  the  U.  S.  Department  of  Agriculture  for  all 
types  of  irrigation  channels  comparisons  of  the  different  index 
methods  have  been  made.  These  results  were  published  in  the 
Journal  of  Agricultural  Research,  Vol.  V,  No.  6,  and  the  numerical 
results  in  the  following  discussion  are  based  on  these  experiments. 
The  U.  S.  Geological  Survey  has  also  secured  a  large  amount  of 
similar  data  on  natural  channels  giving  generally  similar  results, 
which,  however,  are  not  as  directly  applicable  to  irrigation 
conditions. 

Current-meter  Practice. — The  usual  index  methods  of  gaging 
are  the  two-point  and  the  single-point  observations.  In  the  two- 
point  method  the  meter  is  held  at  0.2  and  0.8  of  the  depth  on 
each  vertical,  *  the  mean  of  the  observed  velocities  being  used 
as  the  mean  for  the  vertical.  In  the  single-point  method  the 
meter  is  held  at  0.6  the  depth  below  the  water  surface.  The 
integration  method  is  also  used.  This  consists  in  moving  the 
meter  vertically  through  the  depth  of  water  at  each  interval  so 
that  the  velocity  at  each  portion  of  the  depth  is  integrated  or 
averaged  in  the  resulting  mean  velocity.  The  vertical  movement, 
if  too  rapid,  has  a  tendency  to  cause  rotation  of  the  cup  type 
of  meter  so  that  the  vertical  velocity  of  the  meter  should  not 
exceed  10  feet  per  minute.  The  meter  should  be  given  an  even 
number  of  complete  vertical  trips  to  secure  a  proper  mean. 
These  conditions  introduce  to  some  extent  a  personal  element  on 
the  part  of  the  observer  which  makes  the  other  more  empirical 


MEASUREMENT  OF  IRRIGATION  WATER       135 


methods  preferable  for  general  practice.  The  use  of  the  two- 
point  method  is  limited  to  depths  of  over  1.5  to  2.0  feet  depend- 
ing on  the  form  of  meter  used,  as  good  results  will  not  be  secured 
if  the  meter  is  set  within  0.3  foot  of  the  bottom  or  of  the  water 
surface.  The  single-point  method  can  be  used  for  smaller 
depths.  Both  of  these  methods  are  based  on  the  fact  that  the 
normal  vertical  velocity  curves  have  the  form  of  parabolas. 
Where  the  conditions  of  flow  are  such  that  the  vertical  velocity 
curves  are  not  normal,  more  detailed  methods,  such  as  the 
multiple-point  or  integration,  are  preferable  although  such  condi- 
tions are  necessarily  unfavorable  for  good  rating  stations.  The 
integration  method  is  limited  to  velocities  of  less  than  4  feet  per 
second  due  to  the  difficulty  of  using  rod  or  cable  meters  without 
guys  with  higher  velocities. 

The  equipment  of  the  meters  used  varies  with  the  conditions. 
For  larger  canals  cable  suspension  with  weights  is  usual,  particu- 
larly where  one  is  working  from  a  bridge  several  feet  above  the 
water.  More  firm  support  can  be  secured  by  the  use  of  a  rod 
meter  with  foot  piece  where  the  observer  is  within  6  or  8  feet  of 
the  bottom  of  the  canal.  The  use  of  rods  with  the  meter  at  the 

TABLE  X. — VARIATION  IN  DISCHARGE  IN  PERCENTAGE  BY  THE  TWO-POINT, 

THE  SINGLE-POINT,  AND  THE  INTEGRATION   METHOD,  COMPARED 

WITH  THE   MULTIPLE-POINT  METHOD 


Two-point  method 

Single-point  method 

Integration  method 

Aver- 

age 

varia- 

Type  of   canal   cross- 
section 

Num- 
ber 
of  ob- 
ser- 
va- 
tions 

Mean 
differ- 
ence 
from 
mul- 
tiple- 
point 

Aver- 
age 
varia- 
tion 
9f  a 
single 
obser- 
vation 

Num- 
ber 
of  ob- 
ser- 
va- 
tions 

Mean 
differ- 
ence 
from 
mul- 
tiple- 
point 

tion 
of  a 
single 
obser- 
vation 
5  per 
cent, 
correc- 

Num- 
ber 
of  ob- 
ser- 
va- 
tions 

Mean 
differ- 
ence 
from 
mul- 
tiple- 
point 

Aver- 
age 
varia- 
tion 
of  a 
single 
obser- 
vation 

tion 

ap- 
plied 

Rectangular  flumes.  .  .  . 

27 

+0.68 

1.45 

27 

+4.90 

2.21 

17 

+  1.06 

1.36 

Concrete-lined       trape- 

zoidal sections  

15 

+0.86 

1.  42 

15 

+4.21 

1.94 

4 

+0.72 

0.93 

Shallow    earth    canals. 

13 

-0.38 

1.08 

13 

+3.11 

3.42 

9 

-0.81 

2.44 

sloping  sides  

Shallow    earth    canals, 

steep  sides 

25 

+  1  05 

1.74 

25 

+5.02 

2.44 

18 

+0.36 

2.15 

Earth  canals,  relatively 

deep  sections  

16 

+  1.07 

1.70 

15 

+6.32 

3.18 

7 

+3.06 

3.78 

Mean  of  all 

96 

+0.73 

1.51 

95 

+4.80 

2.54 

55 

+0.76 

2.07 

136  IRRIGA  TION  S Y STEMS 

lower  end  of  the  rod  can  be  employed  for  smaller  depths  at  low 
velocities  or  for  integration.  Current  meters  can  now  be  secured 
equipped  for  each  of  these  three  forms  of  suspension  and  such 
general  purpose  meters  are  to  be  preferred  for  canal  work.  For 
high  velocities  light  wire  guys  are  used  to  hold  the  meter  in  place. 

Table  X,  taken  from  the  article  previously  referred  to,  gives 
the  results  of  comparisons  of  these  different  methods  of  use  of 
current  meters.  This  shows  both  the  two-point  and  integration 
method  to  give  average  results  within  1  per  cent.  The  single- 
point  method  gives  results  about  5  per  cent,  too  high  in  canals; 
when  a  correction  of  this  amount  is  made,  the  results  of  individual 
measurements  have  a  somewhat  higher  probable  error  than  with 
the  other  methods.  Further  detailed  comparisons  indicated  that 
the  two-point  method  gives  equally  good  results  for  different 
velocities,  depths  and  values  of  n.  The  results  with  the  single- 
point  method  appeared  to  vary  slightly  with  the  velocity.  The 
integration  method  gave  the  best  results  for  velocities  of  from 
2  to  3  feet  and  for  the  greater  depths. 

Another  practice  occasionally  used  is  the  three-point  method, 
observations  being  made  at  depths  of  0.2,  0.6  and  0.8.  As  the 
0.6  observation  is  less  accurate  than  the  mean  of  0.2  and  0.8 
observations,  its  inclusion  with  them  will  reduce  the  average 
resulting  accuracy,  so  that  its  use  is  not  to  be  recommended.  A 
greater  number  of  verticals  with  the  two-point  method  is  pre- 
ferable to  a  fewer  number  with  the  three-point  method. 

Use  of  Surface  Floats. — A  number  of  observations  were  also 
made  with  surface  floats.  Such  observations,  while  rough,  are 
frequently  of  use  where  other  methods  are  not  available.  For 
divisions  between  canals  or  turnouts  where  the  sum  of  the  parts 
can  be  compared  with  the  total,  such  rough  methods  may  be 
used.  It  is  customary  to  apply  an  assumed  coefficient  to  the  ob- 
served maximum  surface  velocity  to  secure  the  mean  velocity. 
Such  coefficients  depend  on  the  size  of  the  canal  and  its  value 
of  n  and  may  vary  from  0.60  to  0.90  under  extreme  condi- 
tions. The  effect  of  the  area  for  cross-sections  of  over  20  square 
feet  is  relatively  small.  Table  XI  gives  the  mean  value  of  such 
coefficients  for  the  values  of  n  found  in  irrigation  channels. 
Small  surface  floats  which  offer  little  exposure  to  the  wind,  such 
as  small  chips  or  leaves,  should  be  used.  Several  should  be 
thrown  into  the  canal  and  the  time  of  the  most  rapid  one  used. 
They  should  be  timed  over  a  length  of  100  feet  or  more.  The 


MEASUREMENT  OF  IRRIGATION  WATER       137 


discharge  is  secured  by  multiplying  the  area  of  cross-section  by 
the  observed  velocity  as  reduced  by  the  use  of  the  proper  coeffi- 
cient. To  select  the  coefficient  an  estimate  of  the  value  of  n  must 
be  made.  While  such  methods  are  rough,  where  the  cross-sec- 
tion is  known  as  in  flumes  the  resulting  discharge  may  be  secured 
with  a  probable  average  error  of  10  per  cent.  For  earth  sections 
the  probable  error  in  estimating  the  area  of  cross-section  may 
increase  the  error  in  the  resulting  discharge  above  this  amount. 

TABLE  XI. — COEFFICIENTS  TO  BE  APPLIED  TO  VELOCITIES  OF  FLOATS  TO 
OBTAIN   MEAN  VELOCITY  IN  CANALS 


Area  of 
water 
cross- 
section 

Value  of  n  in  Kutter's  formula 

0.012 

0.014 

0.016 

0.018 

0.020 

0.022 

0.024 

0.026 

0.028 

0.030 

Square 
feet 

2  
4  
6 

0.85 
0.86 
0.87 
0.88 
0.88 
0.89 
0.90 
0.91 
0.91 
0.91 

0.80 
0.81 

0.82 
0.83 
0.83 
0.84 
0.85 
0.86 
0.86 
0.86 

0.76 
0.77 
0.78 
0.79 
0.79 
0.80 
0.81 
0.82 
0.82 
0.82 

0.73 
0.74 
0.74 
0.75 
0.76 
0.77 
0.78 
0.78 
0.79 
0.79 

0.70 
0.71 
0.71 
0.72 
0.73 
0.74 
0.75 
0.75 
0.76 
0.76 

0.67 
0.68 
0.68 
0.69 
0.70 
0.71 
0.72 
0.73 
0.73 
0.73 

0.65 
0.66 
0.66 
0.67 
0.68 
0.69 
0.70 
0.71 
0.71 
0.71 

0.63 
0.64 
0.64 
0.65 
0.65 
0.66 
0.67 
0.68 
0.69 
0.69 

0.61 
0.62 
0.63 
0.63 
0.64 
0.65 
0.66 
0.66 
0.67 
0.67 

0.60 
0.61 
0.62 
0.62 
0.63 
0.64 
0.65 
0.65 
0.66 
0.66 

8  
10  
15 

20  
25  
50  
Over  50 

Number  of  Points  of  Observation. — Comparisons  were  also 
made  to  determine  the  effect  on  the  accuracy  due  to  the  use  of 
varying  number  of  observation  verticals.  In  the  detailed  gag- 
ings  averages  of  16  verticals  were  used;  these  were  compared  with 
the  results  using  only  alternate  and  also  only  every  fourth  verti- 
cal. The  use  of  8  verticals  gave  an  average  difference  of 
about  2  per  cent,  and  the  use  of  4  verticals  of  about  6  per  cent, 
from  the  results  secured  with  16  verticals.  The  results,  however, 
varied  with  the  form  of  section  as  shown  in  Table  XII.  The 
errors  due  to  the  use  of  fewer  verticals  are  less  in  flumes  and  lined 
sections  than  in  earth  canals.  This  is  due  both  to  the  errors  in 
cross-section  due  to  the  use  of  fewer  depths  as  well  as  to  errors 
due  to  fewer  velocity  observations.  For  equal  accuracy  about 
twice  as  many  verticals  should  be  used  in  earth  canals  as  in 
flumes. 

Just  as  two  points  in  the  vertical  velocity  curves  have  been 
found  to  give  the  mean,  it  was  thought  that  possibly  two  points 


138 


IRRIGATION  SYSTEMS 


TABLE  XII.  — EFFECT  ON  THE  ACCURACY  OF  CURRENT-METER 
GAGINGS  OF  VARYING  NUMBERS  OF  VERTICALS 


Aver- 

Num- 

age 
nxim- 

Comparisons  using  one- 
half  of  observed  verticals. 

Comparisons  using  one- 
fourth  of  observed  verti- 

ber of 

,),*.,;! 

berof 

Variation  (per  cent.) 

cals.  Variation  (per  cent.) 

Type  of  canal 

detail 
gag- 

verti- 

ings 
made 

cals  in 
detail 

Aver- 

Minimum and 

Aver- 

Minimum and 

gag- 
inga 

age 

maximum 

age 

maximum 

Flumes,  vertical  sides.  . 

23 

15 

0.9 

+0.05  to  -3.82 

2.9 

0        to  -7.50 

Concrete-lined    canals; 

steeply  sloping  sides.  . 

11 

14 

0.9 

-0.04  to  -2.95 

2.9 

-1.08  to  -5.85 

Concrete-lined     canals, 

wide  and  flatly  sloping 

sides  

6 

17 

1.4 

—  0.37  to  —3.22 

3.8 

—  0.70  to  —6.52 

Average    earth    canals. 

eloping  sides  

18 

16 

2.9 

+0.1    to  -8.3 

9.2 

-1.5    to  -17.6 

Average    earth    canals, 

steep  sides  

21 

16 

2.5 

+0.1    to  -7.3 

9.0 

—0.4    to  -21.1 

Earth  canals,  relatively 

deep  sections     

10 

16 

2.7 

—0.5    to  —5.5 

7.7 

—  0.6    to  —19.4 

Mean  of  all  

89 

16 

1.9 

6.2 

in  the  horizontal  velocity  curve  could  be  found  which  would  give 
the  mean  velocity.  It  was  found  that  in  sections  with  vertical 
sides,  two  verticals  located  from  one-fifth  to  one-sixth  the  width 
from  the  sides  gave  results  within  an  average  of  2.5  per  cent,  of 
that  obtained  from  16  verticals.  In  lined  sections  with  sloping 
sides  similar  results  were  secured  at  from  one-fifth  to  one-fourth 
the  width  of  the  water  surface  from  the  sides,  if  the  area  of  the 
cross-section  were  secured  from  the  known  cross-section.  In 
earth  canals  such  methods  gave  much  larger  errors. 

Gages. — Staff  gages  used  by  the  operating  force  are  more 
usually  graduated  in  feet  and  hundredths  than  in  feet  and  inches. 
Readings  are  made  to  the  nearest  hundredth  or  two-hundreths 
on  small  deliveries;  on  large  canals  this  is  also  usual,  although 
half -tenths  may  be  used.  To  avoid  the  confusion  of  fine  gradua- 
tions, gages  similar  to  standard  yard  or  meter  sticks  may  be 
used,  as  shown  in  Fig.  14*  These  can  be  read  easily  to  the 
nearest  0.02  point.  Where  used  on  large  systems  in  quantities 
these  can  be  made  with  power  saws  and  painted  at  a  cost  of 
about  6  cents  per  foot.  For  small  gages  such  as  are  attached 
to  gate  stems  for  the  purpose  of  giving  the  height  of  opening, 
small  graduated  brass  strips  about  %  inch  wide  perforated  for 
nailing  may  be  used.  Enamelled  gages  have  also  been  used  on 


MEASUREMENT  OF  IRRIGATION  WATER       139 


some  systems,  with  various  marking  schemes.  For  weirs  of 
different  lengths  the  gages  may  be  graduated  to  read  discharges 
directly  instead  of  heads.  The  length  of  weir  to  which  each  gage 
applies  should  be  plainly  marked  on  the  gage. 

Automatic  gages  are  used  at  more  important  points  in  order 
to  secure  continuous  records.  The  fluctuations  which  such 
gages  have  to  cover  are  less  than  in  river  practice  so  that  full- 
scale  readings  are  usual.  There  are  a  number  of  such  registers  on 
the  market,  varying  widely  in  quality  and  price.  The  sheets 
generally  supply  a  week's  record.  The  time  scale  is  usually 
about  2  inches  per  day.  The  price  of  such  registers  varies  from 


12'lnch  Weir  f 

"T     81* 

•I  *C 

—Is 

S     83" 

14 

E-1.0 

•1  33, 

___                . 

?5 

fl 

0            » 

^.5 

•«•: 

•*•• 

!  '7; 

o 

J-lui 

«  2*  » 

18'lnch  Weir 

OS.F. 

I 

.21; 

I5 

1 

•23  ' 

1-2 

'S3: 

i.25 

o 

*    5 

1.25 

___ 

' 

i1?!  '" 

^-     | 

Is'" 

— 

!.33  ' 

*—  "™  *        09 

,H; 

"ZT-3 

a 

3.43*  " 

I  I 

.52 

—  k" 

Ul 

5 

«  2*  » 

j 

Style  No.l  Style  No.2 

FIG.  14. — Forms  of  staff  gages. 

$25  to  over  $100  each,  depending  on  the  character  of  the  clock 
mechanism  and  mechanical  workmanship.  Cheaper  gages 
giving  24-hour  records  can  be  devised  locally  from  ordinary 
clocks. 

Notes  and  Records. — Hydrographic  field  notes  are  preferably 
taken  in  loose-leaf  books  due  to  the  danger  of  loss  or  wetting. 
Current-meter  notes  can  be  taken  on  ordinary  instrument  note 
sheets,  specially  ruled  and  headed  paper  being  used  where  many 
gagings  are  being  made.  The  forms  used  by  the  U.  S.  Geological 
Survey  are  well  suited  to  canal  work.  Where  many  seepage  tests 
are  being  made  a  form  (Fig.  15)  similar  to  that  used  by  the  Twin 
Falls  Canal  Co.  may  be  of  use. 


140 


IRRIGATION  SYSTEMS 


A  blank  form  on  which  the  daily  distribution  of  water  between 
laterals  can  be  shown  is  used  on  many  systems.  This  may  be 
arranged  for  either  weekly  or  monthly  periods.  The  gaging 
stations  may  be  listed  vertically  with  the  dates  horizontally  or 
the  reverse  arrangement  may  be  used.  Where  gage  heights  are 
telephoned  to  the  main  office  each  day,  double  columns  are  used, 
one  to  record  the  gage  height  as  received  and  one  for  the  corre- 
sponding discharge.  Such  a  tabulation  shows  the  division  of 
water  between  laterals  and  is  used  in  making  changes  to  meet 


HYDROGRAPHIC  OPERATIONS  TWIN  FALLS  CANAL  CO. 
Twin  Falls,  Idaho 
Patp                                                                 Sheet  No. 

Diversions  and  Intakes  Between 
Station                                and  Station 

DIVERSIONS 

INTAKES 

NO. 

SEC.FT. 

NO.              SEC.FT. 

NOTATIONS 

|  ^"~- 

r  —  -~~^-  —  • 

,  «.  

—_       '                   '          ~~ 

TOTAL 

NOTATIONS 

Sec.  ft.  discharge  at  Sta.  (upper) 

Sec.ft.discharge  at  Sta.(lower  ) 

Difference 

Diversions  less  Intakes  (sec.ft.) 

Seepage  and  Evaporation  iu  Section(sec.ft 

Seepage  acd  Evaporation  per  mile  (sec.  ft.) 

Per  Cent.  Loss  per  mile 

FIG.  15. — Form  used  for  seepage  tests,  Twin  Falls  Canal  Co. 

the  next  day's  demands.  On  some  systems  each  ditch  rider 
may  make  a  daily  report  in  which  each  delivery  for  the  day  is 
listed.  This  serves  a  similar  purpose  within  the  individual 
beats  that  the  summary  form  does  for  the  whole  system. 

Various  forms  for  summarizing  the  results  of  records  secured  are 
used.  The  monthly  sheets  for  each  station  may  be  totalled  and 
a  seasonal  record  compiled  showing  the  total  flow  at  each  station 
expressed  in  total  acre  feet  or  reduced  to  acre-feet  per  acre 
irrigated.  The  records  may  be  assembled  to  show  the  total 
diversions  into  the  system,  its  division  to  laterals  and  to  indi- 


MEASUREMENT  OF  IRRIGATION  WATER       141 

vidual  deliveries,  waste  from  canals  in  operation  and  other  data. 
The  water  not  accounted  for  is  generally  listed  as  seepage  and 
evaporation;  the  term  "  in  visible  loss"  which  is  sometimes  used 
is  perhaps  more  descriptive,  as  such  items  include  any  errors  in 
records  as  well  as  actual  seepage  losses. 

MEASUREMENT  OF  INDIVIDUAL  DELIVERIES 

The  conditions  of  delivery  to  individual  farms  are  not  gener- 
ally favorable  for  either  accurate  or  convenient  measurement  of 
the  water  used.  The  difficulty  of  securing  dependable  records 
at  costs  within  the  value  of  the  results  has  retarded  the  use  of 
such  measurements  beyond  the  time  when  their  advantages  and 
desirability  have  been  recognized. 

Conditions  Affecting  Accuracy. — The  requirements  of  accuracy 
vary.  Greater  accuracy  is  needed  where  the  supply  is  limited, 
or  where  operation  and  maintenance  charges  are  based  on  the 
records  of  quantities  supplied,  rather  than  on  the  acreage  irri- 
gated. Actual  accuracy  may  be  secondary  to  consistency  where 
the  measurements  are  used  only  to  divide  available  supplies 
proportionately  among  those  entitled  to  receive  water.  It  is 
probable  that  what  may  be  called  consistency  is  usually  more 
important  than  technical  accuracy.  If  weirs  are  used  on  all 
deliveries  and  are  all  subject  to  about  the  same  extent  of  silting 
of  the  pools  during  the  season,  so  that  the  discharge  for  any  given 
head  on  the  weir  is  increased,  due  to  the  increase  in  the  velocity 
of  approach,  the  division  of  the  water  to  the  different  users  may 
still  be  consistently  proportional.  If  some  weirs  silt  and  others 
become  submerged,  due  to  natural  checking  below  the  weirs 
from  weed  growth  or  other  causes,  inconsistent  results  will  be 
obtained,  as  some  will  over-discharge  due  to  silting  and  some 
under-discharge  due  to  submergence. 

Records  of  individual  deliveries  and  of  many  canal  rating 
stations  are  computed  from  gage  readings  secured  once  per  day 
or  sometimes  twice  per  day.  Over  long  periods  of  time  it  is 
probable  that  little  error  results,  as  daily  fluctuations  may  tend 
to  balance.  Where  under  rotation  methods  of  delivery  only 
from  one  to  three  or  four  gage  readings  per  run  may  be  secured 
for  individual  farms,  such  errors  may  not  balance.  Under  some 
conditions  there  may  be  periodic  daily  fluctuations.  Gage 
readings  taken  at  a  regular  time  each  day  may  not  be  representa- 

UNIVERSITY  OF  CALIFORNIA 
DEPARTMENT  OF  CIVIL  ENGINEERING 


142  IRRIGATION  SYSTEMS 

tive  of  the  mean.  Gages  are  usually  read  by  the  ditch  riders. 
Honesty  of  reading  can  be  obtained  and  filling  in  of  missed  read- 
ings practically  prevented  by  proper  supervision.  Errors  in 
reading  cannot  be  avoided.  These  may  tend  to  balance. 

On  individual  deliveries  measurements  are  usually  made  at 
the  time  water  is  turned  in.  With  some  types  of  orifices  this 
may  give  erroneous  results.  For  submerged  orifices  delivering 
into  relatively  large  or  long  farm  ditches  some  time  may  be 
required  until  the  ponding  back  on  the  orifice  becomes  stable. 
This  results  in  reading  too  low  a  gage  on  the  lower  side  and  giving 
too  great  a  discharge  reading.  Another  condition  frequently 
encountered  is  to  have  the  irrigator  begin  irrigating  on  the  checks 
next  to  the  delivery  which  are  often  higher  than  those  further 
in  the  field.  This  may  cause  checking  back  on  the  measuring 
device,  which,  if  a  submerged  orifice  headgate  type,  will  not 
draw  as  much  water  from  the  ditch  as  will  be  the  case  later  on 
the  lower  checks.  Measurements  when  checking  back  will  show 
less  than  the  average  discharge. 

These  various  errors  in  securing  records  are  a  necessary  con- 
dition with  any  device  dependent  on  gage  readings,  no  matter 
how  accurate  it  may  be  in  its  hydraulic  properties.  It  is  question- 
able if  one  is  warranted  in  attempting  to  secure  hydraulic  accu- 
racy out  of  proportion  to  the  practical  accuracy  of  use.  The 
elements  of  error  in  use  cannot,  from  their  nature,  be  reduced  to 
percentages;  hydraulic  errors  more  often  can.  The  resulting 
seasonal  records  on"  any  individual  delivery  which  are  within  5 
per  cent,  of  correct  can  be  considered  very  satisfactory.  If 
average  errors  of  5  per  cent,  with  ordinary  maximum  errors  of 
10  or  12  per  cent,  can  be  obtained  on  a  system  as  a  whole,  the 
results  would  be  fully  as  good  as  those  now  secured  under  present 
actual  practice. 

Cost  of  Operation  of  Measuring  Devices. — Besides  first  cost 
the  expense  of  operation  must  be  considered  in  selecting  measur- 
ing devices.  Maintenance  of  the  structures  themselves  is 
similar  to  the  maintenance  of  other  small  structures  on  the 
system.  Cleaning  of  approach  channels  during  the  season  may 
be  needed  for  those  devices  requiring  low  velocities  of  approach. 
The  principal  costs  of  operation  are  those  connected  with  secur- 
ing and  computing  the  records.  It  is  usually  found  that  the 
ditch  tenders  can  secure  the  gage  readings  needed  without  any 
additional  cost.  If  such  readings  are  taken  at  the  time  of  his 


MEASUREMENT  OF  IRRIGATION  WATER       143 

regular  visits  to  the  turnouts,  the  additional  time  required  to 
read  and  record  gages  is  such  a  small  proportion  of  the  time  re- 
quired to  reach  and  adjust  the  turnout  that  no  reduction  in  the 
area  covered  per  ditch  rider  is  required  on  account  of  such  read- 
ings. The  additional  cost  of  measurement  is  then  mainly  the 
office  or  computing  cost.  The  number  of  turnouts  whose  records 
can  be  computed  and  notices  kept  up  by  one  man  varies  with 
the  type  of  device  and  frequency  of  readings  secured.  Where 
submerged-orifice  headgates  are  used  under  semicontinuous  flow 
or  informal  rotation  methods,  one  computer  should  handle  about 
400  turnouts,  including  the  making  of  monthly  statements  to 
each  user  of  the  water  received  each  month.  Such  devices 
require  more  time  and  labor  in  computing  than  devices  such  as 
weirs.  For  submerged  devices  the  difference  of  two  gage  read- 
ings is  used  to  secure  the  discharge.  If  an  orifice  is  of  the  head- 
gate  or  variable  size  of  opening  type,  an  additional  reading,  from 
which  to  secure  the  size  of  opening,  is  required.  Some  examina- 
tion of  the  height  of  opening  and  the  lower  gage  to  make  sure 
that  the  orifice  is  actually  submerged  may  be  necessary.  This 
detail  requires  time  and  reduces  the  number  of  turnouts  for 
which  one  man  can  make  the  computations.  Where  deliveries 
are  made  by  methods  giving  water  to  each  turnout  about  one- 
half  the  time  over  weirs  or  fixed  opening  orifices,  one  computer 
should  compile  the  records  and  monthly  statements  for  about 
700  turnouts  where  daily  readings  are  secured.  If  readings  are 
not  secured  daily  1,000  turnouts  may  be  handled. 

Other  types  of  devices  are  not  in  use  in  sufficient  numbers  on 
large  projects  to  make  available  data  in  regard  to  the  number 
which  can  be  handled  by  one  computer.  Any  device  requiring 
the  use  of  weekly  charts,  such  as  an  automatic  register,  will 
require  much  more  labor  in  placing  the  chart  and  reducing  the 
record.  Such  registers  are  used  on  canal  rating  stations.  The 
expense  of  reduction  of  the  record  will  be  greater  than  for  single 
daily  readings  if  the  fluctuations  on  the  chart  are  closely  com- 
puted. If  such  fluctuations  are  not  computed,  there  is  no  ad- 
vantage in  the  use  of  a  continuous  chart  record  over  the  single 
readings.  The  expense  of  operation  of  any  types  of  chart  record- 
ing automatic  registers  now  available  will  prevent  their  general 
use  on  individual  deliveries.  The  first  cost  of  such  registers  has 
also  prevented  their  use  for  individual  deliveries  up  to  the 
present  time. 


144 


IRRIGATION  SYSTEMS 


Devices  which  integrate  the  discharge  record  should  be  cheaper 
to  operate.  Daily  readings  would  be  needed  only  for  purposes 
of  checking  the  rate  of  discharge,  the  monthly  quantities  being 
taken  from  the  dial  or  other  means  used  to  indicate  the  total 
quantity  passed,  in  the  same  way  that  monthly  quantities  are 
secured  on  gas  or  electric  meters.  Computations  of  such  results 
would  consist  mainly  of  the  expense  of  making  out  the  monthly 
statements. 

Devices  which  regulate  and  hold  constant  the  rate  of  dis- 
charge require  less  labor  in  computation  of  results  than  any 
devices  except  the  self-integrating  type.  Only  the  time  elements 
need  to  be  recorded  for  such  devices.  From  this  point  of  view 
such  devices  should  be  desirable;  from  the  point  of  view  of  canal 
operation  and  regulation,  they  may  not  be  desirable. 

The  usual  rate  of  pay  for  computers  is  about  $90  per  month. 
The  cost  of  computing  measurements  of  individual  deliveries  for 
different  assumptions  is  shown  in  Table  XIII. 

TABLE  XIII. — ESTIMATED  AREA  FOR  WHICH  COMPUTATIONS  OF  WATER  DE- 
LIVERY CAN  BE  MADE  BY  ONE  MAN  AND  RESULTING  COST  PER  ACRE 


Number  of  deliv- 
eries handled  by 
one  computer 

Area  in  acres  for  which  one  man 
can  make  computations  of  delivery 
for  average  area  served  per  turnout 
of 

Cost  per   acre  per   season   of  7 
months  for  computer  at  $90  per 
month  for  average  area  served  per 
turnout  of 

20  acres 

40  acres 

80  acres 

20  acres 

40  acres 

80  acres 

400 
700 
1,000 

8,000 
14,000 
20,000 

16,000 
28,000 
40,000 

32,000 
56,000 
80,000 

$0.077 

0.045 
0.032 

$0.039 

0.022 
0.016 

$0.020 
0.011 
0.008 

The  annual  cost  of  depreciation,  interest  and  maintenance  for 
devices  of  different  first  costs  serving  different  average  areas  is 
given  in  Table  XIV.  The  annual  cost  is  estimated  for  both  wood 
and  concrete  structures.  Interest  was  taken  at  6  per  cent., 
depreciation  at  10  and  3  per  cent,  and  maintenance  at  5  and  3 
per  cent,  for  wood  and  concrete  respectively.  This  gives  total 
annual  costs  of  21  and  12  per  cent,  of  the  first  cost  for  wood  and 
for  concrete  devices.  For  the  more  expensive  devices  the  per- 
centage for  maintenance  taken  may  be  too  high. 

These  figures  give  some  indication  of  the  annual  costs  per 
acre  to  be  expected  under  different  conditions.  Separate  struc- 
tures for  measuring  devices  cannot  be  built  under  usual  condi- 
tions for  less  than  $10  or  $15,  even  for  small  weirs  or  orifices. 


MEASUREMENT  OF  IRRIGATION  WATER       145 


TABLE  XIV. — ANNUAL  COST  OF  INTEREST,  DEPRECIATION,  AND  MAINTE- 
NANCE FOR  MEASURING  DEVICES  UNDER  DIFFERENT  CONDITIONS 


For   a   total 
cost  of  meas- 
uring devices 
installed  of 

Wood  device,   estimated  annual 
cost  21  per  cent,  of  first  cost 

Concrete  devices,  estimated  annual 
cost  12  per  cent,  of  first  cost 

Annual 
cost 
per 
device 

Cost  per  acre  for  '  average 
area  in  acres  served  per 
device  of 

Annual 
cost 
per 
device 

Cost  per  acre  for  average 
area  in  acres   served  per 
device  of 

20  acres 

40  acres 

80  acres 

20  acres 

40  acres 

80  acres 

$  5 

$1.05 

$0.05 

$0.03 

$0.01 

$0.60 

$0.03 

$0.02 

$0.01 

10 

2.10 

0.10 

0.05 

0.03 

1.20 

0.06 

0.03 

0.02 

15 

3.15 

0.16 

0.08 

0.04 

1.80 

0.09 

0.045 

0.02 

25 

5.25 

0.26 

0.13 

0.07 

3.00 

0.15 

0.075 

0.04 

35 

7.35 

0.36 

0.18 

0.09 

4.20 

0.21 

0.105 

0.05 

50 

10.50 

0.52 

0.26 

0.13 

6.00 

0.30 

0.15 

0.075 

75 

15.75 

0.79 

0.39 

0.20 

9.00 

0.45 

0.22 

0.12 

Measuring  devices  are  usually  installed  by  the  canal  company. 
This  is  essential  if  they  are  to  be  properly  selected  and  set. 
The  individual  user  may  be  required  to  bear  the  expense  directly; 
it  is  more  usual  to  include  it  in  general  cost,  however.  If  built 
by  the  canal  company  it  is  preferable  that  the  device  be  located 
within  the  right  of  way  in  order  that  a  more  complete  control 
may  be  exercised.  The  advantage  in  reducing  the  number  of 
turnouts  or  increasing  the  area  served  per  turnout  is  shown  by 
these  tables.  Under  rotation  delivery  it  is  sometimes  possible 
to  use  one  measuring  device  to  measure  the  irrigation  head  for 
several  farms.  This  is  possible  on  laterals  where  only  one  irriga- 
tion head  is  used  and  where  the  seepage  loss  in  the  lateral  is  small. 
The  cost  of  measurement  can  be  greatly  lessened  if  structures 
necessary  for  other  purposes  can  also  be  used  for  measurement. 
This  is  done  on  many  systems  where  the  turnout  is  of  a  headgate 
type  which  can  be  used  as  a  submerged  orifice.  These  may  not 
be  very  satisfactory  measuring  devices  from  a  hydraulic  point 
of  view,  yet  the  limitation  of  costs  may  make  them  the  only  type 
practicable. 

As  an  example,  a  system  may  be  taken  on  which  the  total 
operation  and  maintenance  cost  averages  $1  per  acre  and  on 
which  it  may  be  considered  desirable  to  install  individual  measur- 
ing devices  if  the  total  cost  will  not  exceed  10  per  cent,  of  other 
operation  costs.  Where  40  acres  would  be  served  per  turnout, 
one  would  be  limited  to  a  type  of  device  costing  $15  if  of  wood, 
for  which  one  computer  could  handle  700  deliveries,  a  require- 
ment which  might  be  fulfilled  by  small  weirs  if  the  fall  needed 
10 


146  IRRIGATION  SYSTEMS 

for  their  use  was  available.  For  such  limiting  costs,  not  over 
$35  each  could  be  spent  for  wooden  devices  for  deliveries  to  80 
acres.  For  concrete  devices  higher  first  costs  could  be  afforded. 
If,  however,  the  turnout  structures  are  of  such  nature  that  they 
can  be  used  for  measurement  without  additional  construction 
cost,  such  as  tube  tap  boxes  extending  through  the  bank,  the 
cost  is  entirely  that  for  operation  which,  even  for  such  turnouts, 
should  be  within  the  limit  given.  The  possible  saving  in  such 
structure  costs  may  make  the  use  of  devices  necessary  which  are 
undesirable  hydraulically  if  measurements  are  to  be  secured 
at  all. 

Under  present  conditions  individual  measuring  devices  costing 
in  excess  of  $25  each  are  not  in  general  use.  For  projects  having 
farms  of  small  size,  the  value  of  water  and  land  are  usually  higher 
and  greater  costs  per  acre  may  be  warranted.  For  such  condi- 
tions one  device  may  serve  more  than  one  holding,  particularly 
for  rotation  methods  of  delivery.  Under  favorable  conditions 
of  construction  and  use,  the  cost  of  both  fixed  charges  and  opera- 
tion of  measuring  devices  may  not  exceed  5  cents  per  acre  per 
year.  They  are  not  now  used  in  many  cases  where  the  annual 
cost  exceeds  10  cents  per  acre.  In  the  future  higher  costs  may 
be  warranted.  For  a  device  to  be  used  to  any  extent  on  individ- 
ual deliveries,  it  must  be  capable  of  installation  at  costs  of  less 
than  $25.  Limited  sales  at  somewhat  higher  costs  may  be 
secured.  For  extensive  use  the  cost  should  not  exceed  $15  each. 

Other  Requirements  of  Measuring  Devices. — In  addition  to  the 
restrictions  in  regard  to  loss  of  head  required  and  cost,  measuring 
devices  must  be  of  such  nature  that  they  are  not  easily  interfered 
with  and  their  principles  must  be  such  that  their  general  action 
can  be  understood  by  the  farmers.  Interference  may  be  of  two 
kinds :  accidental  and  intentional.  Accidental  interference  results 
mainly  from  clogging  with  weeds  or  other  drift.  Devices  which 
permit  the  passage  of  drift  and  which  do  not  need  to  be  pro- 
tected by  screens  are  much  preferable.  Weirs  are  quite  satis- 
factory in  this  regard,  submerged  orifices  less  so,  but  much  pref- 
erable to  most  of  the  special  devices.  Intentional  interference 
results  from  efforts  on  the  part  of  individual  users  to  secure  more 
water  than  they  are  entitled  to  or  to  secure  some  water  without 
having  it  recorded  by  the  measuring  device.  Weirs  and  fixed 
area  orifices  are  not  subject  to  such  interference  with  the  device 
itself.  The  quantity  received  may  be  affected  by  changes  in  the 


MEASUREMENT  OF  IRRIGATION  WATER       147 

control  gates,  but  this  is  not  directly  the  fault  of  the  measuring 
device.  The  discharge  through  orifices  can  be  affected  by 
changes  in  the  submergence.  Any  device  depending  for  its 
action  upon  floats  is  subject  to  tampering  unless  securely  housed. 
Such  housing  adds  to  the  cost.  Various  types  of  floating  weirs 
have  been  devised  which  will  give  constant  discharges  with 
varying  levels  in  the  supply  ditch.  It  is  doubtful  if  such  devices 
will  give  satisfactory  results  under  general  conditions  of  use  as 
the  discharge  can  be  increased  by  adding  to  the  weights  of  the 
float.  To  be  really  successful  a  measuring  device  must  be 
acceptable  to  the  users.  This  will  retard  and  probably  prevent 
the  general  use  of  more  complicated  devices,  even  though  their 
cost  could  be  reduced  so  as  to  bring  them  into  direct  competition 
with  weirs  and  orifices. 

On  many  systems  the  fall  available  for  measuring  devices  is 
limited.  Unless  there  is  considerable  fall  to  the  land,  there  will 
be  little  excess  fall  between  the  canal-water  surface  and  the  land 
when  delivery  is  being  made  unless  the  canal  banks  are  carried 
higher  than  is  required  for  other  purposes.  A  device  which  can 
operate  on  a  small  and  variable  head  or  fall  has  a  distinct  ad- 
vantage. The  amount  of  fall  required  is  the  principal  disad- 
vantage of  weirs.  The  ability  to  operate  on  small  available 
heads  is  an  advantage  of  submerged  orifices  which  often  over- 
balances other  disadvantages  of  operation.  Some  loss  of  head 
through  turnouts  is  always  required ;  it  may  be  possible  to  use 
this  loss  as  a  basis  for  measurement  with  orifice  types  of  headgates. 

These  various  requirements  of  use,  particularly  that  of  cost, 
have  practically  limited  the  use  of  irrigation  devices,  up  to  the 
present  time  at  least,  to  some  form  of  weir  or  submerged  orifice. 
Under  special  conditions  other  devices  are  used,  but  consider- 
ing irrigation  practice  as  a  whole,  measurement  is  limited  to 
weirs  and  simple  submerged  orifices  as  separate  structures  or 
combined  with  the  turnout  structure.  Many  special  devices 
are  constantly  being  developed,  both  for  measurement,  recording 
quantities  and  for  controlling  the  rate  of  discharge,  some  of 
them  of  merit  and  much  ingenuity,  but  as  yet  none  of  them  has 
possessed  a  sufficiently  complete  combination  of  low  cost,  sim- 
plicity, and  dependability  to  enable  it  to  secure  any  general 
adoption.  The  conditions  of  use  vary  too  widely  for  any  one 
device  to  be  suited  to  all  of  them.  For  a  given  set  of  conditions 
there  is  usually  some  one  form  of  weir  or  orifice  which  is  the  best 


148 


IRRIGATION  SYSTEMS 


for  such  use.     It  is  not  to  be  expected  that  any  special  devices 
will  ever  have  as  wide  a  field  as  these  more  standard  types. 


WEIRS 

Weirs  which  are  used  in  irrigation  practice  are  of  three  types: 
Cippoletti,  rectangular  contracted  and  rectangular  suppressed. 
There  are  other  types,  such  as  triangular  weirs,  which  are 
accurate  for  purposes  of  measurement.  For  the  quantities  of 
water  used  in  irrigation  the  loss  of  head  required  by  triangular 
weirs  is  too  great  to  enable  this  type  to  be  used. 

The  Cippoletti  weir  (Plate  VI,  Fig.  A)  is  the  type  most  gener- 
ally used.  Its  formula  is  based  on  having  a  discharge  propor- 
tional to  the  length,  the  outward  slope  balancing  the  effect  of  the 
contractions.  The  discharge  of  the  rectangular  contracted  weir 
is  usually  computed  by  the  Francis  formula,  the  length  being 
reduced  by  an  amount  equal  to  0.2  of  the  head  as  a  correction 
for  the  two  end  contractions.  If,  as  is  necessary  if  the  Francis 
formula  is  used,  the  head  is  limited  to  not  over  one-third  the 
length,  this  correction  for  contraction  will  be  a  maximum  of 
6.6  per  cent.  For  weirs  used  in  irrigation,  recent  exact  measure- 
ments by  Mr.  V.  M.  Cone  show  little  difference  between  the 
Cippoletti  and  rectangular  contracted  weir  in  regard  to  accuracy. 

If  the  head  on  the  weir  exceeds  one-third  the  length  of  the 
weir,  numerous  experiments  have  shown  that  the  usual  formulas 
give  discharges  smaller  than  the  actual,  the  error  increasing  as 
the  ratio  of  head  to  length  increases.  It  is  preferable  to  choose 
the  length  of  the  weir,  so  that  for  maximum  expected  discharges 

TABLE  XV. — CAPACITIES  OF  WEIRS  OF  DIFFERENT  LENGTHS 


Discharge  in   second-feet   when 

head  is  equal  to  one-third  the 

Minimum  fall  in  feet 

Length 
of  crest 
in 
feet 

length 

Depth  required  on  90° 
triangular  weir  to  give 
the  same  discharge  as 
Cippoletti  weir,  feet 

required  for  satisfac- 
tory use  of  Cippoletti 
or  rectangular  con- 
tracted   weirs  to 

Head  in 

Cippoletti 

Rectangu- 
lar   con- 

feet 

weirs 

tracted 

capacity  given 

weirs 

1.0 

0.33 

0.64 

0.58 

0.58 

0.50 

1.5 

0.50 

1.78 

1.65 

0.87 

0.60 

2.0 

0.67 

3.69 

3.41 

1.17 

0.75 

3.0 

1.00 

10  01 

9  32 

1.00 

4  0 

1  33 

20  66 

19  07 

1.25 

5.0 

1.67 

36.33 

33.53 

1.50 

PLATE  VI. 


FIG.  A. — Eighteen-inch  Cippoletti  Weir. 


FIG.  B. — Weir  with  gage  graduated  to  read  discharge  directly,  Twin  Falls 
Salmon  River  System. 

(Facing  page.  148.) 


PLATE  VI. 


FIG.  C. — Headgate  with  sharp  edged  ori-        FIG.  D. — Dethridge"  Meter  installed  in 
fice  set  in  front  wall,  Minidoka  project,    laboratory  of    California    Experimental 

Station  at  Davis. 


FIG.  E. — Double  orifice  headgate  graduated  to  show  discharge  in  miners, 
inches,  used  in  Idaho. 


MEASUREMENT  OF  IRRIGATION  WATER       149 

the  head  will  not  exceed  this  limit,  although  tables  are  now  avail- 
able for  actual  discharges  at  higher  heads.  Table  XV  shows  the 
maximum  discharges  of  weirs  of  different  lengths  when  the  head 
is  one-third  of  the  length. 

The  loss  of  head  required  for  a  weir  without  submergence  for 
such  conditions  of  maximum  discharge  will  be  equal  to  one- 
third  the  length.  If  the  water  surface  in  the  ditches  below  the 
weirs  could  be  exactly  located  or  was  uniform  during  the  season, 
weirs  might  be  built  with  their  crests  at  such  elevations  that  this 
minimum  loss  of  head  could  be  realized.  Practically,  of  course, 
this  cannot  be  done.  Weirs  can  be  submerged  to  a  considerable 
percentage  of  the  head  without  seriously  affecting  the  result. 
The  correction  for  different  percentages  of  submergence  as  usually 
given  is  shown  in  Table  XVI. 

TABLE  XVI. — CORRECTION  IN  DISCHARGE  OF  WEIRS  DUE  TO  SUBMERGENCE 


Submergence,  per  cent,  of  head 


Corrections  to  be  applied  to  discharge  for 
same  head,  unsubmerged,  per  cent. 


10 
20 
30 
40 
50 


-  1 

-  2 

-  6 
-10 
-16 


These  figures  indicate  that  submergence  up  to  one-fourth  the 
head  can  be  permitted  without  exceeding  a  correction  of  5  per 
cent.  This  permits  the  weir  crest  to  be  set  lower  than  would 
otherwise  be  the  case.  By  having  a  gage  below  the  Weir  on 
which  submergence  can  be  read,  submergence  up  to  40  per  cent, 
of  the  head,  particularly  if  not  of  usual  occurrence,  may  be  per- 
missible. Estimated  minimum  falls  which  should  be  available 
are  also  given  in  Table  XV.  For  small  weirs  at  least  6  inches 
should  be  available.  For  the  larger  weirs  some  submergence 
may  be  permissible.  In  case  less  fall  is  available  than  is  needed 
for  the  measurements  of  quantities  suited  to  a  given  length  of 
weir,  longer  weirs  will  reduce  the  fall  required  for  the  same 
discharge.  This  is  shown  in  Table  XVII. 

Rectangular  weirs  with  contractions  suppressed  are  desirable 
types  if  considered  from  the  hydraulic  point  of  view  alone.  In 
irrigation  practice  they  are  more  directly  affected  by  silting, 
which  changes  the  height  of  the  crest.  The  smaller  sizes  also 


150 


IRRIGATION  SYSTEMS 


TABLE    XVII. — LENGTH    OF   CIPPOLETTI  WEIRS   IN   FEET   REQUIRED   TO 

CARRY   DIFFERENT   DISCHARGES   WITHOUT  SUBMERGENCES,  LENGTHS 

ABOVE  1.5  FEET  VARIED  BY  FEET 


Fall 

Discharge  to  be-  carried,  second-feet 

available 

feet 

1.00 

2.00 

4.00 

6.00 

10.00 

0.50 

1.5 

2.0 

4 

5 

9 

0.60 

1.5 

1.5 

3 

4 

7 

0.75 

1.5 

1.5 

2 

3 

5 

1.00 

1.5 

1.5 

2 

3 

3 

require  more  material  for  their  construction,  except  when  used 
in  rectangular  channels  such  as  flumes.  It  is  usual  with  Cippo- 
letti  and  contracted  rectangular  weirs  to  build  the  weir  notch 
in  the  upstream  wall  of  the  structure  and  to  enlarge  the  ditch 
above  to  reduce  the  velocity  of  approach.  The  weir  structure 
then  consists  of  the  wall  containing  the  weir  notch  with  such 
length  of  flume  on  the  downstream  side  as  may  be  required  to 
prevent  injury  from  the  falling  water. 

This  difference  in  material  required  for  the  different  types  can 
be  illustrated  by  the  standards  used  by  the  U.  S.  Reclamation 
Service.  These  are  made  for  the  use  of  2-inch  planks  and 
4X4  posts.  The  use  of  2-inch  plank  is  desirable  for  all  struc- 
tures set  in  the  ground,  and  is  particularly  so  for  weirs  where 
the  rigidity  of  the  structure  is  relied  on  to  keep  the  weir  crest 
true.  For  Cippoletti  weirs,  up  to  3-foot  crests,  the  length  of 
structure  is  4  feet;  for  crests  of  from  4  to  10  feet,  it  is  6  feet.  In 
firm  soil  with  good  cutoffs  shorter  lengths  may  be  used.  The 
structures  for  suppressed  weirs  are  of  similar  material  and  twice 
the  length  of  those  for  Cippoletti  weirs.  The  data  taken  from 
the  Reclamation  Service  standards  is  shown  in  Table  XVIII. 

Cippoletti  weirs  require  slightly  greater  amounts  of  lumber 
than  rectangular  contracted  weirs,  due  to  the  greater  width  of 
box  made  necessary  by  the  sloping  ends.  For  small  weirs  con- 
siderably more  material  is  required  for  suppressed  weirs  than  for 
either  of  the  other  types.  For  the  larger  sizes  the  stilling  pool 
of  the  Cippoletti  and  rectangular  contracted  weirs  becomes  so 
wide  that  the  additional  material  needed  in  the  upper  wall  ex- 
ceeds that  used  in  the  longer  box  of  the  suppressed  weir.  Ex- 
pressed in  terms  of  capacity  the  material  required  for  suppressed 
weirs  is  always  greater  than  for  the  other  two  types.  For  the 


MEASUREMENT  OF  IRRIGATION  WATER       151 


TABLE  XVIII. — COMPARISON  OF  MATERIAL  REQUIRED  (U.  S.  RECLAMATION 
SERVICE  STANDARD  TYPES  OF  WEIRS)  AND  CAPACITY  OF  DIFFERENT 

WEIRS 


Length  of  weir 
crest  in  feet 

Approximate  quantity  of  material  required  for  different  types  of 
weirs,  in  feet,  B.M. 

Cippoletti 

Contracted 
rectangular 

Suppressed 
rectangular 

1.0 

130 

120 

175 

1.5 

130 

130 

190 

2.0 

145 

135 

220 

3.0 

250 

250 

355 

4.0 

640 

630 

665 

5.0 

750 

715 

705 

6.0 

785 

765 

750 

7.0 

905 

875 

785 

heights  of  crest  obtainable  under  usual  ditch  conditions,  less 
depth  on  suppressed  weirs  can  be  secured,  giving  less  capacity 
for  the  larger  sizes  of  this  type  of  weir. 

The  pools  above  weirs  should  be  sufficiently  large  to  effec- 
tively reduce  the  velocity  of  approach.  Where  weirs  are  set  below 
headgates,  at  least  20  feet  distance  from  the  headgate  outlet  to 
the  weir  is  needed  even  with  wide  pools  unless  baffles  are  used. 
For  purposes  of  control  by  the  canal  company  it  is  preferable  to 
place  the  weirs  within  the  right  of  way.  Where  this  is  done  it 
may  limit  the  length  of  pool  which  may  be  secured.  The  width 
of  the  bottom  of  the  pool  should  be  at  least  2  feet  greater  than 
the  length  of  the  crest. 

Costs  for  small  weirs  cannot  be  figured  in  terms  of  the  unit 
quantities,  such  as  lumber  or  excavation.  The  proportion  of  the 
cost  represented  by  the  assembling  of  material  and  men  is  neces- 
sarily a  large  proportion  of  the  total.  Where  large  numbers  of 
weirs  of  standard  types  are  to  be  used,  it  is  profitable  to  install 
a  central  yard  with  power  saws,  at  which  all  the  material  required 
for  a  single  structure  can  be  assembled  and  cut  to  proper  lengths. 
The  structure  may  be  partly  erected  before  hauling  if  the  ex- 
pense of  hauling  is  not  increased.  Crews  for  placing  small  weirs 
usually  vary  from  3  to  6  men.  Weirs  up  to  2-foot  crests  can 
usually  be  installed  for  $15  each;  3-foot  crests  for  about  $18. 
The  cost  may  be  divided  with  about  30  per  cent,  excavation  and 
backfill,  40  per  cent,  material  and  erection,  and  30  per  cent. 


152  IRRIGATION  SYSTEMS 

overhead  and  setting  gages.  These  figures  are  taken  from  costs 
on  systems  where  several  hundred  have  been  built  under  average 
conditions  of  cost  of  material.  For  the  actual  material  used  in 
small  weirs  the  costs  run  from  $60  to  over  $100  per  M.,  B.M.  if 
excavation-  and  all  other  costs  are  divided  by  the  lumber  used. 
On  larger  weirs  the  unit  cost  figured  on  the  basis  of  the  lumber 
used  will  be  less. 

SUBMERGED  ORIFICES 

The  orifice  was  the  earliest  type  of  measuring  device  used  in 
the  West,  the  miner's  inch  being  the  legal  unit  of  measurement 
in  most  of  the  States.  While  still  retained  in  use,  the  miner's 
inch,  or  inch  as  it  is  more  frequently  called,  is  now  defined  as  a 
certain  proportion  of  a  second-foot,  which  in  reality  makes  the 
second-foot  the  standard.  The  old  miner's  measurements  were 
made  with  unsubmerged  orifices.  Where  there  is  sufficient  fall 
available  for  an  orifice  without  submergence,  other  types,  par- 
ticularly weirs,  are  preferable. 

Submerged  orifices  have  the  advantage  of  requiring  a  smaller 
loss  of  head  than  weirs  and  of  not  being  affected  by  conditions 
which  affect  the  depth  of  submergence  without  changing  the 
difference  of  head,  such  as  checks,  in  the  ditch  below  the  orifice. 
Where  the  elevation  of  the  water  surface  above  the  orifice  is 
fixed,  changing  the  water  surface  below  the  orifice  changes  the 
difference  of  head  acting  on  the  orifice  and  affects  the  discharge. 
Orifices  may  have  a  fixed  area  or  an  adjustable  opening.  For 
measurement  purposes  the  fixed  area  is  preferable,  as  this  can 
be  given  sharp  edges  which  result  in  more  definite  coefficients 
and  computations  can  also  be  more  easily  made,  as  one  variable 
is  eliminated.  Fixed  openings  where  variable  flow  is  to  be 
measured  have  the  disadvantage  that  for  small  discharges  the 
difference  of  head  may  be  less  than  sufficient  for  satisfactory 
measurement  if  the  opening  is  made  large  enough  to  handle  the 
larger  flows. 

In  many  cases  delivery  gates  are  used  as  submerged  openings 
for  purposes  of  measurements.  This  is  done  to  save  the  cost  of 
separate  structures  as  well  as  to  utilize  the  head  necessarily  lost 
through  the  headgate  and  thus  avoid  the  additional  loss  of  head 
necessary  for  separate  devices.  Such  measurements  are  less 
dependable  than  those  made  at  special  structures ;  they  are  much 
more  cheaply  secured,  however.  The  cost  of  installation  and 


MEASUREMENT  OF  IRRIGATION  WATER       153 

maintenance,  which  is  shown  in  Table  XIV  to  be- the  principal 
cost  of  measuring  devices,  is  avoided,  as  the  turnout  would  be 
required  for  delivery,  whether  measurements  are  needed  or  not. 
For  many  conditions  of  use  the  increase  of  accuracy  of  separate 
measuring  devices  over  what  may  be  obtained  by  properly  con- 
structed orifice  headgates  may  not  be  sufficient  to  justify  the 
expense. 

Discharge  through  orifices  is  based  on  the  formula: 

Q  =  AV  =  CA-^2gh 

where  C  is  an  experimental  coefficient ;  h  is  the  difference  in  eleva- 
tion of  the  water  surface  above  and  below  the  orifice  when  sub- 
merged, and  the  elevation  of  the  water  surface  above  the  center 
of  the  opening  for  free  fall;  A  is  the  area  of  the  opening.  The 
greatest  difficulty  in  the  use  of  this  formula  is  in  the  proper  selec- 
tion of  the  coefficient  of  discharge.  For  sharp-edge  fully  con- 
tracted orifices,  the  value  is  fairly  consistent  and  has  been  found 
from  many  experiments  to  be  about  0.61.  Under  field  conditions 
values  as  high  as  0.65  have  been  found.  Where  the  orifice  is 
placed  near  to  the  sides  or  bottom  of  the  approach  channel,  where 
the  edges  of  the  orifices  are  not  sharp,  where  the  length  is  too 
great  in  proportion  to  the  height  of  opening,  as  in  gates  set  with 
small  openings,  or  where  the  difference  in  head  is  sufficient  to 
produce  velocities  sufficiently  high  through  the  orifice,  so  that 
for  the  depths  available  the  water  below  the  orifice  is  unduly  dis- 
turbed, it  has  been  found  that  the  coefficients  are  higher  than 
for  standard  sharp-edged  orifices  and  that  for  such  conditions 
the  coefficient  tends  to  vary  for  different  gates  apparently  similar 
but  affected  to  different  extents  by  such  uncertain  elements.  For 
ordinary  headgate  orifices  a  mean  value  of  the  coefficient  of  from 
0.70  to  0.75  is  usually  found  with  rather  wide  individual  varia- 
tions. For  headgates  set  in  openings  in  the  bank,  a  coefficient 
of  0.70  is  probably  representative;  for  gates  set  at  the  upper  ends 
of  tubes  extending  through  the  banks,  a  value  of  0.75  may  be 
preferable.  Where  the  conditions  are  such  that  a  gradual  in- 
crease in  the  velocity  as  the  water  approaches  the  gate  is  secured, 
the  coefficient  may  have  values  as  high  as  0.80.  Where  gates 
are  used  as  orifices,  they  should  all  be  made  as  nearly  similar  as 
possible  and  a  sufficient  number  rated  under  the  conditions  of 
use  to  determine  the  mean  coefficient. 

In  general  where  the  available  head  is  sufficient  for  the  use  of 


154 


IRRIGATION  SYSTEMS 


a  weir,  it  will  be  used  in  preference  to  an  orifice,  if  separate  meas- 
uring devices  are  to  be  built.  An  available  difference  of  head 
of  0.2  is  needed  for  orifices.  Orifices  are  not  generally  used  for 
small  deliveries  if  falls  over  0.50  are  available  or  for  larger  sizes 
for  falls  over  0.75  feet.  The  discharge  of  sharp-edged  orifices 
(coefficient  0.61)  for  various  areas  of  openings  and  differences  in 
head  are  shown  in  Table  XIX.  These  figures  can  be  used  as  a 
basis  for  the  selection  of  the  size  of  orifice  for  different  conditions. 
For  orifices  having  higher  coefficients,  the  capacity  will  be  in- 
creased in  proportion  to  the  increase  in  coefficient. 

TABLE  XIX. — DISCHARGE  IN  SECOND-FEET  OF  SHARP-EDGED  ORIFICES  UNDER 
DIFFERENT  CONDITIONS  (C  =  0.61) 


Area  of  orifice 

Discharge  in 

second-feet  for 
head  of 

differences  in 

Approximate  quantity  of 
lumber  required  in  feet, 

in  square  feet 

0.2  feet 

0.5  feet 

0.75  feet 

structures   of   U.  S.    Re- 
clamation Service 

0.25 

0.55 

0.86 

150 

0.5 

1.09 

1.73 

150 

1.0 

2.19 

3.46 

4.24 

170 

1.5 

3.28 

5.19 

6.36 

170 

2.0 

4.38 

6.92 

8.48 

200 

This  table  indicates  that  the  quantity  of  lumber  required  for 
such  orifices  is  not  very  different  than  that  shown  in  Table  XVIII 
for  weirs  of  similar  capacity  when  heads  of  more  than  0.5  feet 
are  available.  For  small  available  falls,  larger  sizes  of  orifices  or 
longer  weirs  are  needed  and  more  material  required  than  for 
devices  of  similar  size  operated  under  greater  falls. 

For  the  same  available  head,  a  given  error  in  reading  the  gage 
produces  less  error  in  the  resulting  discharge  for  orifices  than  for 
weirs.  This  is  due  to  the  fact  that  the  discharge  for  orifices 
depends  on  the  one-half  power  of  the  head,  where  for  weirs  it 
is  the  three-halves  power  of  the  head.  For  similar  capacities, 
the  actual  difference  in  head  on  an  orifice  will  usually  be  less  than 
on  a  weir,  so  that  the  actual  errors  are  in  favor  of  the  orifice  but 
to  a  less  extent. 

Several  different  types  of  orifice  headgates  are  used.  In 
some  of  the  open  types,  the  gate  is  set  at  the  front  of  the  turn- 
out structure  (Plate  VI,  Fig.  D).  For  such  gates  the  lateral 
from  which  water  is  taken  serves  as  the  stilling  pool  to  reduce  the 
velocity  of  approach.  In  others  the  gate  is  set  3  or  4  feet  back 


MEASUREMENT  OF  IRRIGATION  WATER       155 

from  the  front  of  the  structure;  the  channel  of  approach,  while 
permitting  more  velocity,  is  definite  in  area  and  if  coefficients 
are  determined  for  the  actual  conditions  of  use,  perhaps  pref- 
erable. The  coefficient  is  liable  to  vary  with  the  rate  of  dis- 
charge unless  velocity  of  approach  is  taken  into  account. 

Variable  coefficients  introduce  complications  in  computation 
which  are  hardly  warranted  by  the  accuracy  obtainable  in  any 
case  by  such  devices.  Setting  the  gate  back  from  the  front  of 
the  structure  gives  a  better  opportunity  for  making  it  tight  when 
closed,  as  earth  can  be  placed  in  front  of  the  gate.  On  some 
systems  the  gate  sill  is  level  with  the  floor  of  the  turnout,  sup- 
pressing the  bottom  contraction.  In  others,  the  gate  rests  on 
bottom  boards  4  to  8  inches  high.  The  sides  are  usually  flush 
with  the  sides  of  the  box,  except  for  the  projection  of  the  guide 
cleats.  One  or  2-inch  thicknesses  are  used  for  the  gates,  giving 
edges  of  those  widths.  A  check  board  may  be  inserted  below 
the  gate  to  insure  submergence  at  all  stages. 

The  height  of  gate  opening  is  read  on  the  gate  stem.  Some 
system  of  marks  or  a  scale  can  be  fastened  to  the  gate  stem  and 
set  so  as  to  read  zero  when  the  gate  is  closed.  The  reference 
mark  for  reading  this  height  of  opening  is  usually  the  top  of  the 
gate  frame. 

A  combination  headgate  and  sharp-edged  orifice  has  been  used 
on  the  Minidoka  project  in  Idaho.  A  fixed-opening  orifice  with 
metal  edges  is  set  in  the  upper  face  of  the  turnout.  The  head- 
gate,  of  the  usual  type,  is  set  about  3  feet  back  from  the  orifice. 
Measurement  is  made  through  the  upper  fixed  orifice,  the  gate 
being  used  for  regulation  purposes.  When  the  full  capacity  of 
the  orifice  is  required,  the  gate  can  be  raised  so  as  not  to  obstruct 
the  flow.  The  necessary  loss  of  head  in  the  turnout  is  then  used 
to  furnish  a  large  part  or  all  of  the  loss  of  head  needed  through 
the  orifice.  The  cost  is  but  little  greater  than  for  the  ordinary 
headgate  alone.  Where  it  is  difficult  to  secure  sufficient  fall 
for  measurement  this  type  of  device  should  prove  of  much  use, 
as  it  has  the  advantages  over  the  headgate  alone  resulting  both 
from  the  fixed  opening  and  the  sharp  edges. 

For  relatively  small  deliveries  through  canal  banks  the  tube 
type  of  turnout  is  more  usual.  This  enables  the  canal  bank  to 
be  used  as  a  road  more  easily,  and  for  large  banks  is  cheaper. 
Gage  readings  for  such  devices  are  taken  above  the  inlet  and 
below  the  outlet,  the  head  lost  being  that  required  for  the  orifice 


156  IRRIGATION  SYSTEMS 

and  for  from  8  to  12  feet  of  tube.  The  coefficients  do  not  differ 
materially  from  those  found  for  other  similar  orifices,  being  in 
general  somewhat  higher.  The  more  usual  sizes  are  10  X  12, 
12  X  12,  and  12  X  18  inches. 

Any  fluctuation  in  the  supply  canal  affects  the  discharge 
through  the  orifices.  To  partially  control  such  fluctuations, 
double  orifices  may  be  used.  The  controlling  gate  may  be  set 
at  the  front  of  the  turnout  with  a  similar  gate  at  the  lower  end. 
The  effect  of  any  fluctuation  in  the  level  of  the  supply  canal  will 
be  divided  between  the  two  orifices.  Where  sufficient  loss  of 
head  is  available  for  this  method,  closer  regulation  may  be 
secured. 

Pipe  turnouts  are  sometimes  used  as  tube  outlets  for  measure- 
ment. The  variation  of  the  shape  of  the  opening  for  partly 
raised  gates  and  the  necessity  for  using  special  tables  for  these 
partial  areas  make  them  less  satisfactory  for  measurement  than 
rectangular  openings.  Such  outlets  more  usually  have  metal 
gates  with  sharp  edges  which  is  an  advantage  in  measurement. 
For  full  openings  the  disadvantages  mentioned  are  not  so 
important. 

SPECIAL  MEASURING  DEVICES 

Much  thought  and  ingenuity  has  been  spent  in  the  design  of 
measuring  devices  for  use  in  irrigation.  Although  a  great  variety 
of  such  devices  have  been  developed,  none,  as  yet,  has  been  able 
to  combine  accuracy,  general  adaptability  and  low  cost  to  a 
sufficient  extent  to  enable  it  to  secure  any  general  adoption. 
While  the  large  number  of  such  devices  that  might  be  used  on 
large  systems,  should  they  be  adopted,  appears  to  furnish  an 
attractive  commercial  opening  for  any  such  successful  device, 
the  price  which  such  systems  feel  justified  in  paying  for  measure- 
ment does  not  leave  a  margin  over  actual  cost  for  devices  which 
have  been  suggested  up  to  the  present  time.  An  increasing 
demand  for  the  measurement  of  water  together  with  a  willing- 
ness to  expend  larger  amounts  for  the  devices  used  for  that  pur- 
pose may  in  the  future  supply  a  commercial  demand  for  devices 
other  than  weirs  and  orifices.  New  devices  are  being  developed 
continually,  tests  of  which  are  being  made  available.  While 
these  are  of  interest,  those  responsible  for  the  selection  of  measur- 
ing devices  for  any  system  will  do  well  to  give  their  attention  to 
the  adaptation  of  some  of  the  forms  of  weirs  or  orifices  to  their 


MEASUREMENT  OF  IRRIGATION  WATER       157 

particular  conditions  rather  than  in  looking  for  new  devices. 
Information  regarding  both  these  more  standard  devices  and 
many  special  ones  is  given  in  various  texts  and  bulletins, 
references  to  which  are  given  at  the  end  of  the  chapter. 

The  Venturi-meter  principle  has  been  adapted  to  irrigation 
conditions.  The  cost  of  construction  and  of  the  recording  de- 
vice has  prevented  its  use  to  any  extent.  It  is  adapted  to  use  with 
pumping  plants  as  the  excess  cost  is  less  where  the  meter  can  be 
built  into  the  pipes  used  with  the  pumps.  The  cost  can  be  some- 
what reduced  by  depending  upon  single  readings  instead  of  using 
a  recording  device.  The  loss  of  head  is  small ;  it  can  be  used  over 
a  considerable  range  of  discharge  or  with  water  carrying  silt; 
the  meter  itself  has  no  parts  to  get  out  of  order  and  the  accuracy 
is  relatively  high.  Efforts  to  reduce  the  cost  by  using  rectangular 
sections  have  been  made  such  as  by  contracting  the  area  vertically 
in  flumes. 

Several  measuring  devices  which  control  the  rate  of  discharge 
have  been  devised.  Under  some  conditions  such  devices  may 
be  desirable.  Where  relatively  small  streams  are  delivered  con- 
tinuously or  where  the  head  is  limited  to  a  certain  maximum 
rate,  a  controlling  device  may  be  preferable.  Where,  however, 
the  taking  of  water  is  not  closely  controlled  so  that  water  may 
be  turned  back  into  the  canal,  devices  which  do  not  increase  their 
discharge  when  the  canal  stage  rises  may  lead  to  breaks  in  the 
banks.  If  other  use  is  not  available  for  such  excess  water  it  is 
preferable  to  have  it  distributed  among  the  other  turnouts  instead 
of  passing  down  the  canal  to  overload  lower  sections. 

Although  the  orifice  with  a  free  discharge  was  the  more  general 
type  in  the  earlier  mining  development,  it  is  used  to  only  a  limited 
extent  at  present  in  irrigation  practice.  The  larger  amount  of 
fall  required  for  free  discharge  makes  the  use  of  submerged 
orifices  more  general.  Where  water  is  delivered  through  pipe 
lines  carrying  light  pressures,  deliveries  can  be  made  through 
such  orifices.  This  condition  exists  on  such  systems  in  southern 
California  and  various  types  of  orifices  with  free  discharge  are  in 
use  there.  For  very  small  deliveries,  meters,  such  as  are  used  in 
water-works  practice,  can  be  used.  This  is  done  in  a  few  cases 
although  such  use  is  very  limited  in  extent. 

The  Dethridge  meter  (Plate  VI,  Fig.  D)  is  in  use  to  a  consider- 
able extent  in  Australia.  It  consists  of  a  drum  on  which  there 
are  projecting  blades,  the  wheel  being  revolved  by  the  water 


158  IRRIGATION  SYSTEMS 

and  measuring  a  given  quantity  of  water  at  each  revolution. 
The  total  quantity  discharged  at  any  given  time  is  secured  from  the 
number  of  revolutions  of  the  wheel  as  recorded  by  a  counter  and 
the  rating  of  the  meter.  This  device  has  the  advantage  that  its 
action  is  easily  understood  and  that  the  cost  of  securing  the 
record  is  relatively  small.  The  cost  of  installation  is  somewhat 
high;  the  cost  of  the  type  used  in  Australia  has  been  about  $40 
each  when  built  in  relatively  large  numbers.  The  rating  is  also 
somewhat  affected  by  the  conditions  of  checking  or  depth  of 
flow  on  the  meter. 

RECORDS  OF  INDIVIDUAL  DELIVERIES 

Computations. — Tables  for  the  discharge  of  weirs  and  orifices 
of  several  kinds  and  of  corrections  for  use  where  the  conditions 
differ  from  the  standard  have  been  printed  in  many  bulletins  and 
books.  These  are  necessarily  more  or  less  general  in  character 
and  expressed  in  different  units.  In  order  to  reduce  computation 
tables  to  the  minimum  size  so  that  they  can  be  used  more  quickly 
it  is  desirable  to  prepare  special  tables  covering  only  the  types 
and  sizes  of  devices  used  on  any  system  expressed  in  the  units 
in  current  use.  These  can  be  prepared  as  tracings  and  prints 
supplied  for  office  and  field  use. 

In  order  to  regulate  deliveries,  the  ditch  riders  need  to  make 
computations  of  the  discharge  in  the  field.  These  do  not  need 
to  be  carried  to  as  close  a  result  as  is  usual  with  the  office  computa- 
tions ;  condensed  tables  which  will  fit  into  the  field  note  books  are 
preferable.  In  some  cases  these  may  also  be  distributed  to  con- 
sumers. Such  tables  can  be  very  conveniently  arranged  for 
weirs  of  different  lengths  or  for  orifices  of  fixed  areas.  For 
orifices  of  variable  area,  more  columns  are  needed  if  field  multi- 
plication is  to  be  avoided  and  the  tables  become  larger.  The 
fewer  the  sizes  and  types  of  devices  in  use,  the  more  simple  are 
the  tables, needed.  Such  simplicity  is  of  material  advantage  to 
the  ditch  riders. 

Tables  for  office  computation  are  needed  both  to  secure  the 
rate  of  flow  and  also  the  total  quantity  delivered  in  any  time. 
Both  computations  may  be  combined  in  one  table  such  as  for 
any  given  length  of  weir  a  table  may  be  prepared  showing  the 
head  on  the  weir  in  the  left-hand  column  and  the  discharge  in 
acre-feet  for  various  periods  of  time  in  the  remaining  columns. 
The  changing  of  rates  of  flow  in  second-feet  per  day  to  acre-feet 


MEASUREMENT  OF  IRRIGATION  WATER       159 

is  comparatively  simple  as  1  second-foot  flowing  for  24  hours 
equals  nearly  2  acre-feet  (1.983  exactly)  or  1  second-foot  equals 
1  acre-inch  per  hour. 

Tables  are  usually  preferable  to  curves  for  routine  computa- 
tions as  they  can  be  used  more  quickly  and  the  results  of  the 
same  measurement  will  always  be  the  same.  In  taking  quantities 
from  curves,  the  interpolations  may  result  in  slightly  different 
results  from  the  same  measurements  as  taken  off  at  different 
times. 

The  computations  for  standard  conditions  are  relatively 
simple.  Any  condition  requiring  the  use  of  a  correction  factor 
not  only  reduces  the  accuracy  but  also  materially  increases  the 
cost  of  computation  due  to  the  additional  time  required.  Veloc- 
ity of  approach  corrections  for  weirs  are  particularly  trouble- 
some to  make,  the  necessity  for  such  corrections  should  be 
avoided  wherever  practicable.  Corrections  for  submergence 
require  the  determination  of  the  percentage  of  submergence. 
This  involves  the  use  of  two  gage  readings.  The  discharge  that 
would  result  with  the  depth  given  by  the  upper  gage  when  not 
submerged  can  be  corrected  by  the  proper  percentage  or  the 
amount  of  submergence  can  be  used  to  determine  the  equivalent 
depth  without  submergence  for  the  same  discharge.  This  latter 
method  requires  a  somewhat  smaller  amount  of  computation. 
Curves  can  be  plotted  from  which  for  any  depth  on  the  upper 
gage^ind  amount  of  submergence  as  shown  by  the  lower  gage, 
the  equivalent  depth  with  free  fall  can  be  secured.  This  latter 
depth  is  used  to  secure  the  corrected  discharge  directly  from  the 
weir  tables.  Corrections  for  such  conditions  as  suppression  of 
contraction  of  orifices  are  fixed  and  are  made  as  a  certain  percent- 
age of  all  discharges.  These  can  be  taken  into  account  in  the 
computations  of  the  discharge  tables,  the  coefficient  used  being 
adjusted  to  the  actual  character  of  the  opening. 

Forms. — Nearly  all  the  forms  used  in  irrigation  practice  relate 
to  the  delivery  of  water  or  its  measurement.  The  records  of 
the  ditch  riders  are  very  largely  of  this  nature.  Among  the  types 
of  forms  used  are  the  various  forms  of  ditch  riders'  reports  to  the 
company  showing  records  of  delivery,  filing  forms  for  office 
records,  and  computation  forms.  The  purpose  of  a  printed 
form  is  to  standardize  the  record  and  reduce  the  labor  and  time 
required  in  securing  data.  Records  filled  in  on  forms  where 
each  item  desired  is  specifically  listed  are  much  more  liable  to  be 


160  IRRIGATION  SYSTEMS 

complete  than  those  taken  as  memoranda.  At  the  same  time, 
the  use  of  forms  should  not  be  carried  so  far  that  data  not  essential 
or  necessary  is  called  for.  A  clearly  arranged,  compact  blank 
form  calling  for  the  minimum  of  items  is  of  much  assistance  in 
securing  good  records.  The  order  of  the  items  on  the  form  should 
be  the  same  as  the  usual  order  of  observation  and  record  in  the 
field.  Forms  for  application  and  notices  of  water  delivery  are 
discussed  in  Chapter  IV. 

Ditch  Riders'  Records. — The  form  of  the  daily  records  of  the 
ditch  riders  depends  principally  upon  the  measurement  of  water. 
Where  no  records  of  individual  deliveries  are  kept,  the  daily 
reports  are  mainly  memoranda  regarding  maintenance,  com- 
plaints or  records  of  canal  gages  and  in  some  cases  no  written 
reports  may  be  required.  Where  individual  measurements  are 
made  the  daily  reports  consist  most  largely  of  the  records  on 
which  the  computations  of  the  quantities  delivered  will  be  made. 
It  is  not  generally  considered  desirable  to  have  the  ditch  riders 
make  such  computations  as  their  selection  is  based  on  other 
qualifications.  They  should  understand  measurement,  however, 
in  order  to  be  able  to  deliver  specified  amounts.  It  is  also  not 
desirable  to  require  or  to  permit  copying  of  field  records  by  the 
ditch  riders.  The  original  field  record  should  be  kept  in  such 
manner  that  it  can  be  submitted  to  the  office  and  if  more  than 
one  copy  is  needed  they  should  be  secured  by  the  use  of  carbons 
in  the  field.  Such  forms  are  usually  bound  in  small  perforated 
books  or  used  in  loose-leaf  holders,  the  former  method  being  more 
usual. 

The  field  records  of  individual  deliveries  may  be  kept  in  two 
general  ways.  In  one  of  these  all  deliveries  on  any  day  are 
recorded  on  a  single  sheet,  or  sheets  by  journal  methods.  In 
the  other  separate  sheets  are  used  for  each  delivery  the  record 
being  added  to  each  day  during  delivery.  The  first  method  is 
usually  preferable  as  the  records  for  each  day  can  be  removed 
from  the  field  book  and  the  loss  of  a  field  book  can  cause  the  loss 
of  only  1  day's  notes.  The  field  records  are  usually  posted  on 
individual  record  cards  in  the  office  which  show  the  complete 
record  to  each  individual  for  the  season.  Where  deliveries  cover 
from  1  to  4  or  5  days  and  occur  at  periods  of  2  weeks  or  more 
the  second  method  may  be  preferable  as  the  complete  record  of 
each  delivery  shows  on  one  sheet.  This  is  also  necessary  if  the 
consumer  is  required  to  sign  the  delivery  sheet. 


MEASUREMENT  OF  IRRIGATION  WATER       161 


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IRRIGATION  SYSTEMS 


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MEASUREMENT  OF  IRRIGATION  WATER       163 


Various  forms  are  shown  in  the  illustrations.  Form  7-308 
(Fig.  16)  of  the  U.  S.  Reclamation  Service  illustrates  the  type  in 
which  all  records  for  a  single  day  are  placed  on  one  sheet;  form 
7-311  (Fig.  17),  the  type  where  one  sheet  is  used  for  each  de- 
livery over  a  longer  period.  In  case  form  7-311  is  used  the  ditch 
rider  may  be  required  to  prepare  daily  reports  on  form  7-308 
by  copying  from  his  field  records.  The  forms  of  the  Twin  Falls 
Canal  Co.,  Fig.  18,  provide  for  entering  the  amount  delivered 
directly  rather  than  the  data  on  which  the  amount  was  computed. 
The  charges  on  this  system  are  not  based  on  the  quantity  re- 
ceived; the  record  is  used  to  limit  quantities  to  J^o  second-foot 
per  acre  average  flow.  The  reverse  side  provides  for  reports  of 


DITCHRIDER'S    DAILY    REPORT 

Lateral 

Number 

Coulee 

Gate 

No. 

Amount 
Flowing 
from 
Oate 

Boar 
Visited 

Remark  3: 

-^—  ^ 

—  -~__ 

1  "  " 

' 

|  1 

This  Is  to  certify  that  the  above  record  is  correct 

COMPLAINTS 


DESCRIPTION 


REPORTS,  ON  LATERALS,  GATES,  AND  OTHER  MATTERS 


FIG.  18. — Form  of  ditch  rider's  daily  report,  Twin  Falls  Canal  Co. 

complaints  and  maintenance  data.  The  form  of-  the  Patterson 
Water  Co.  provides,  Fig.  19,  for  measurement  either  by  gate 
under  pressure  or  by  open  flow  referred  to  under  the  column 
"Water"  as  width  and  depth  and  also  includes  columns  for 
computation.  The  form  of  the  Yolo  County  Consolidated  Water 
Co.,  Fig.  20,  is  also  arranged  so  that  the  charges  can  be  carried 
out  on  the  field  report.  Forms  for  separate  sheets  for  each  user 
are  illustrated  by  those  of  the  San  Joaquin  and  Kings  River  Canal 
and  Irrigation  Co.,  Fig.  21,  and  of  the  Sacramento  Valley  West 
Side  Canal  Co.,  Fig.  22;  the  latter  is  secured  in  duplicate.  The 
form  used  by  the  San  Luis  Power  &  Water  Co.,  Fig.  23,  is  tacked 
to  each  weir.  Both  ditch  rider  and  water  user  record  the  flow 


164 


IRRIGATION  SYSTEMS 


3 


H 
P3 


W   C3 


i  i 

H    P5 


s  § 

P    J 


I 

J^ 

O 


H 
H 


MEASUREMENT  OF  IRRIGATION  WATER       165 


and  time  whenever  the  weir  is  visited,  the  gages  being  graduated 
to  give  quantities  direct.     At  the  end  of  each  week  the  water 


YOLO  COUNTY  CONSOLIDATED  WATER  COMPANY 
Daily  report  by                                                                                                                                     1913 

WATER  USER 

TURNED  ON 
Date                    Hour 

TURNED  OFF 
Date                   Hour 

Head  in 
Feet 

Total 
Hours 

Price  per 
Hour 

AMOUNT 

ACRES 

CROP 

—  - 

—  •           —  

'  



•  —  ••  —  r 

" 

FIG.  20. — Ditch  rider's  daily  report,  Yolo  County  Consolidated  Water  Co. 

user  signs  the  card  which  is  then  turned  in  to  the  office.     The 
ditch  rider  also  keeps  his  own  record  in  his  field  book. 


FORM  9< 

Secti 
Cana 
Wate 
For  s 

an 

20M-7-V2      V  &  G 

County 

Gate  No 

r  or< 
ccou 

iered  1 
nt  of 

jy  —                                             _ 

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R 

SEC 

LOTS 

ACRES 

Crop 

Soil 

Distai 

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m  Cans 
Ditch 

tj 

Condit 

Date 

191 

Hour 

Hours 
Flow 

MEASUKEMENTS 

Upper 

Lower 

Depth     Width 

Turned  on 

M 

Measured 

M 

_•• 

"~7T  ' 

— 

TT] 

'  —  -  — 

—  -  —  -•  

'  —  ~~~~~1 

—  -_—  -, 

Turned  off 

M 

No. 

ZANJERO 

FIG.  21. — Ditch  rider's  report  of  individual  deliveries,   San  Joaquin  and 
Kings  River  Canal  &  Irrigation  Co. 

In  some  cases  books  containing  a  number  of  different  forms 
may  be  bound  for  use  by  the  ditch  riders.  These  may  be  used 
for  the  data  for  a  definite  period,  usually  a  week,  or  the  leaves 


166 


IRRIGATION  SYSTEMS 


may  be  removable  as  filled.  In  addition  various  tables  of 
measurement  of  water  or  rules  and  regulations  of  the  canal 
company  may  be  bound  with  the  forms.  The  forms  of  the 
Idaho  irrigation  district  are  well  suited  to  systems  handled  with 


, 

[ 

en 

B 

o 

j 

S 

;; 

i 

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FORE  OPERATED  BY 

SAL  COMPANY  . 

Renort  Nn. 

c 

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z 
0 

IIF  WATER  SUPPLY  WAS  SHORT  MAKE  FULL  EXPLAINAT 
ON  THE  BACK  OF  THIS  SHEET  AS  TO  REASON  WHY 

I  hereby  approve  the  foregoing  repor 

OWNER  OR  WATER  USER 

'J 

i 
( 

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c3                  ' 

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less  detail  than  is  used  with  some  other  forms  of  organization. 
A  sheet,  Fig.  24,  is  used  for  each  gate  for  each  month,  the  record 
for  the  remainder  of  the  month  being  on  the  reverse  side.  De- 
liveries are  made  on  request  from  the  water  user  on  the  form 


MEASUREMENT  OF  IRRIGATION  WATER       167 


II1 

I  .§  "t 
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IRRIGATION  SYSTEMS 


1912                      JULY 

1912 

AMOUNT  OF  RIGHT        '                        GATE  NUMBER 

Name 

Description  of  Laud  Served 

GATE  LOCATION 

P 

< 

n 

Received  Order 
Number 

Complied  With 
Order  No. 

Quantity  Running 

Quantity 
Running 

Before 

After 

i 

2 

,^x*- 

10 

—  .  •  — 

r~  —  *  —  i 

1  '  —  1 

-~—^-~- 

l»_  —  —  -^ 

—  i 

11 

12 

13 

• 

FIG.  24. — Monthly  record  sheet  for  each  water  delivery,  Idaho  irrigation 

district. 


TO  THE  WATERMASTER 

OF  THE  IDAHO  IRRIGATION  DISTRICT: 


Turn 


(ON 


inches  of  water  for  the  undersigned 


at  this  gate  (No.) ,  on  the. day  of 

1914 


Dated 1914 


Eeceived  at  Gate  No. 

Date   ..  1914 


Time  Received 


;A.M. 

i  P.M. 


Complied  with  the  within  order  by 

C  ON 
turning  J  Q^f Inches  on  the 

_day  oL 1914 

The  amount  of  water  running  at 
the  above  gate  after  complyiug  with 
this  order  ia___  .__.  inches 


Signed 


FIG.  25. — Form  for  request  for  water  delivery  and  record  of  ditch  rider, 
Idaho  irrigation  district. 


MEASUREMENT  OF  IRRIGATION  WATER       169 


__acres  1 
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170  IRRIGATION  SYSTEMS 

shown  on  Fig.  25.  The  water  master  fills  out  the  reverse  side 
of  the  request  giving  a  record  of  that  delivery.  The  record  of 
the  ditch  rider's  book  is  also  filled  out.  For  each  month  the 
record  sheet  and  cards  for  each  gate  are  filed  together  and  furnish 
a  record  of  the  delivery  for  that  period. 

Water  Ledger  Cards. — Various  forms  of  individual  water 
records  are  used.  The  data  required  for  any  one  season  can 
usually  be  contained  on  a  5  X  8  card  and  such  card  systems  are 
generally  preferable  to  book  systems.  The  cards  can  be  filed 
by  land  descriptions,  key  numbers  or  owners'  names.  Owners' 
names  are  usually  preferable  as  the  charges  are  carried  to  the 
ledgers  under  such  names.  Change  of  ownership  requires  a 
change  in  filing  order  of  the  record  if  names  are  listed  alpha- 
betically. This  can  easily  be  done  with  card  systems.  On  large 
systems  it  is  more  convenient  to  subdivide  the  water-record 
files  by  ditch-rider  beats,  arranging  all  owners  under  each  beat 
alphabetically.  The  field  records  are  received  by  such  beats  and 
are  more  easily  entered  by  using  such  divisions.  Key  maps 
showing  each  turnout,  owners'  names  and  divisions  between  beats 
are  used  with  such  systems.  The  form  used  by  the  U.  S. 
Reclamation  Service,  Fig.  26,  for  such  records  is  typical.  This 
is  ruled  for  use  on  both  sides  of  the  card,  with  a  place  for 
monthly  summaries  on  the  reverse  side. 

REFERENCES  FOR  CHAPTER  V 

BULLETINS  BY  STATE  AGENCIES 

Arizona. — SMITH,  G.E.P. — Weirs  for  Irrigating  Streams,  1906,  Timely  Hints 
for  Farmers,  No.  57,  Arizona  Agricultural  Experiment  Station,  Tucson, 
Ariz. 

California. — Some  Measuring  Devices  Used  in  the  Delivery  of  Irrigation 
Water,  1915,  Bulletin  247,  California  Agricultural  Experiment  Station, 
Berkeley,  Cal. 

Colorado. — CARPENTER,  L.  G. — The  Measurement  and  Division  of  Water, 
1894,  Bulletin  27,  State  Agricultural  College,  Fort  Collins,  Colo. 

CONE,  V.  M. — The  Colorado  Statute  Inch  and  Some  Miner's  Inch  Measur- 
ing Devices,  1915,  Bulletin  207,  Colorado  Agricultural  Experiment 
Station,  Fort  Collins,  Colo. 

CONE,  V.  M.— The  Dethridge  Meter,  1915,  Bulletin  215,  Colorado  Agri- 
cultural Experiment  Station,  Fort  Collins,  Colo. 

Idaho. — BARK,  D.  H. — The  Measurement  of  Irrigation  Waters,  1912, 
Extension  Bulletin  3,  Idaho  Agricultural  Experiment  Station,  Moscow, 
Idaho. 

Montana. — FORTIER,  S. — Farmers'  Weirs,  1902,  Bulletin  34,  Montana 
Agricultural  Experiment  Station,  Bozeman,  Mont. 


MEASUREMENT  OF  IRRIGATION  WATER       171 

KNEALE,    R.   D. — Measurement  of   Water,    1913,   Circular  24,    Montana 

Agriculture  College,  Bozeman,  Mont. 
Nevada. — KEARNEY,  W.  M. — Table  of  Discharge  over  Cippoletti    Weirs, 

1914,  Pamphlet  6,  State  Engineer's  Office,  Carson  City,  Nev. 
New  Mexico. — BIXBY,  F.  L. — Tests  of  Submerged  Orifice  Headgates,  1915, 

Bulletin    97,    New    Mexico    Agricultural    Experiment    Station,    State 

College,  N.  M. 
Utah. — LYMAN,  R.  R. — Measurement  of  Flowing  Streams,  1912,  Bulletin 

5,   Utah  Engineering  Experiment  Station,   University  of  Utah,   Salt 

Lake  City,  Utah. 
WINSOR,  L.  M. — Measurement  and  Distribution  of  Irrigation  Water,  1912, 

Circular  6,  Utah  Agriculture  College,  Logan,  Utah. 
Washington. — WALLER,  O.  L. — How  to  Measure  Water,  1914,  Circular  1, 

Engineering  Division  of  the  Extension  Department,  State  College  of 

Washington,  Pullman,  Wash. 
Wyoming. — FLEMING,  B.  P. — The  Measurement  of  Water  for   Irrigation, 

1902,  Bulletin  53,  Wyoming  Experiment  Station,  Laramie,  Wyo. 

GOVERNMENT  PUBLICATIONS 

U.  S.  Reclamation  Service. — Measurement  of  Irrigation  Water,  with  Tables, 

1913,  U.  S.  Reclamation  Service,  Washington,  D.  C. 

SANFORD,  G.  O. — The  Measurement  of  Water  to  Farm  Units,  1909,  Opera- 
tion and  Maintenance  Conference,  Powell,  Wyo. 
CROWNOVER,  C.  E. — Importance  of  Measurement  of  Water,   1911,  First 

Conference  of  Operating  Engineers,  Boise,  Idaho. 
LONGWELL,  J.  S. — Measurement  to  Farm  Units,  1913,  Second  Conference  of 

Operating  Engineers,  Boise,  Idaho. 
LONGWELL,   J.   S. — Why   Accurate  Hydrographic   Data  are   Essential  to 

Proper    Operation    and    Maintenance,    1915,    Fourth    Conference  of 

Operating  Engineers,  Boise,  Idaho. 
STEWARD,   W.  G. — Hydrometric  Problems  Encountered  on  an  Irrigation 

Project,  1915,  Fourth  Conference  of  Operating  Engineers,  Boise,  Idaho. 
U.  S.  Geological  Survey. — HORTON,  R.  E. — Weir  Experiments,  Coefficients 

and  Formulas,  1907,  Water  Supply  Paper,  200. 
JONES,  B.  E. — A  Method  of  Correcting  River  Discharge  for  a  Changing 

Stage,  1916,  Water  Supply  Paper  375. 
HALL,  M.  R.,  HALL,  W.  E.,  AND  PIERCE,  C.  H. — A  Method  of  Determining 

the  Daily  Discharge  of  Rivers  of  Variable  Slope,  1915,  Water  Supply 

Paper  345. 
Journal  of  Agricultural  Research,  Washington,   D.   C. — HARDING,   S.  T. — 

Experiments  in  the  Use  of  Current  Meters  in  Irrigation  Canals,  Vol.  V, 

No.  6. 
CONE,  V.  M. — Flow   through   Weir  Notches  with  Thin  Edges  and  Full 

Contractions,  Vol.  V,  No.  23. 

CONE,  V.  M. — A  New  Irrigation  Weir,  Vol.  V,  No.  24. 
ADAMS,  F.— Delivery  of  Water  to  Irrigators,    1910,    Bulletin  229,  Office 

Experiment  Stations,  U.  S.   Department  of  Agriculture,  Washington, 

D.  C. 


172  IRRIGATION  SYSTEMS 

GENERAL  REFERENCES 

HOYT  AND  GROVER. — River  Discharge,  John  Wiley  Sons,  New  York. 
MEAD,    E. — An   Australian   Irrigation   Ditch   Water    Meter,    Engineering 

News,  March  26,  1908. 
STEVENS,  J.  C. — Experiments  on  Small  Weirs  and  Measuring  Modules, 

Engineering  News,  Aug.  18,  1910. 
STEVENS,  J.  C. — Hydrometry  as  an  Aid  to  Successful  Operation,   1911, 

Transaction  American  Society  Civil  Engineers,  Vol.  LXXI. 
HANNA,  F.  W. — Irrigation  Management,  Engineering  News,  Feb.  15,  1912. 
GIBB,  A.  S. — Use  of  the  Cippoletti  Weir  for  Ascertaining  the  Discharges  of 

Irrigation  Water  Courses,  1912,  Punjab  Irrigation  Branch  Paper,  14. 
STEWARD,  W.  G. — Water  Measuring  Devices,  Journal  of  Idaho  Society  of 

Engineers,  June,  1912. 

STEWARD,  W.  G. — Some  Methods  of  Measuring  Water  on  U.  S.  Reclama- 
tion Service,  Engineering  and  Contracting,  Aug.  21,  1912. 
STEWARD,  W.  G. — Measuring  and  Recording  Devices  for  Irrigation  Systems, 

Engineering  News,  Aug.  29,  1912. 
LTMAN,  R.  R. — Why  Irrigation  Water  Should  be  Measured,  Engineering 

News,  Oct.  17,  1912. 
ALLISON,  J.  C. — Selling  Water  by  Current  Meter  Measurement,  Engineering 

News,  Jan.  9,  1913. 
WRIGHT,  A.  E. — Methods  and  Devices  for  Measuring  Water  for  Irrigation 

Engineering  and  Contracting,  May  21,  1913. 
LONGWELL  AND   STEWARD. — Experiments  in  Weir  Discharge,  1913,  Vol. 

LXXVI,  Transactions  American  Society  Civil  Engineers. 
LYMAN,  R.  R. — Measurement  of  the  Flow  of  Streams  by  Approved  Forms 

of  Weirs  with  New  Formulae  and  Diagrams,  Vol.  LXXVII,  Transaction 

American  Society  Civil  Engineers,  December,  1914. 


CHAPTER  VI 
RULES  AND  REGULATIONS 

The  majority  of  the  larger  canal  systems  find  it  desirable  to 
adopt  a  set  of  rules  and  regulations  covering  the  operation  of  their 
systems  and  to  print  these  for  distribution  among  the  water  users. 
This  is  also  done  by  a  number  of  smaller  systems.  The  laws  of 
some  of  the  States  require  that  this  be  done  in  the  case  of  irriga- 
tion districts.  The  public  utility  commissions  also  have  juris- 
diction over  the  character  of  service  as  well  as  the  rates  charged 
by  public  utility  irrigation  companies.  The  Railroad  Commis- 
sion of  California  in  several  cases  has  outlined  rules  which  were 
considered  to  cover  the  essentials  of  good  service  on  particular 
systems.  Printed  rules  and  regulations  are  used  by  some  sys- 
tems in  all  the  States  although  their  use  is  probably  more  general 
in  California  due  to  the  greater  number  of  commercial  companies 
and  irrigation  districts  operating  there. 

On  large  systems,  some  uniform  practice  in  the  delivery  of 
water  and  control  of  the  canal  is  required.  Such  practice  can 
be  embodied  in  the  rules  and  regulations  so  that  each  land  owner 
under  the  system  may  have  a  basis  for  judging  whether  he  is 
receiving  the  service  to  which  he  is  entitled.  Such  rules  may  also 
be  of  much  assistance  to  the  ditch  riders  when  refusing  to  permit 
violations  of  the  rules,  as  a  definite  policy  as  shown  by  the  regu- 
lations eliminates  much  chance  for  favoritism  and  usually  results 
in  greater  uniformity  of  service. 

Rules  and  regulations  should  be  clear,  concise  and  to  the 
point.  They  should  be  confined  to  the  more  essential  points 
as  too  many  minor  regulations  tend  to  reduce  the  relative  im- 
portance of  the  more  essential  rules.  The  rules  usually  adopted 
can  be  divided  into  two  general  classes:  those  governing  the 
relations  between  the  users  and  the  company,  and  those  specify- 
ing the  duties  of  the  ditch  riders.  Copies  of  the  latter  class  are 
frequently  supplied  to  the  users,  as  they  have  an  interest  in  the 
extent  of  the  authority  and  the  duties  of  the  ditch  riders  with 
whom  they  come  directly  into  contact.  The  by-laws  and  in 

173 


174  IRRIGATION  SYSTEMS 

some  cases  the  articles  of  incorporation  of  the  company,  par- 
ticularly for  cooperative  companies  and  irrigation  districts,  are 
frequently  printed  with  the  rules  and  regulations.  In  some  cases 
the  rules  of  operation  may  be  included  in  the  by-laws  although 
it  is  preferable  to  confine  the  by-laws  to  such  matters  as  the 
place  of  business,  meetings  of  officers,  and  the  election,  titles, 
and  duties  of  the  various  officers,  leaving  the  preparation  or 
modification  of  rules  and  regulations  to  .the  officers  selected  for 
their  enforcement.  With  commercial  companies  certain  of  the 
more  important  points  involving  delivery  of  water  and  operation 
of  the  system  may  be  included  in  the  water-right  contracts. 
This  is  desirable  from  the  consumer's  point  of  view  as  they  do 
not  have  control  over  the  officers  of  these  companies  such  as 
they  do  have  in  the  various  cooperative  forms  of  organization. 
Where  commercial  companies  come  within  the  classification  of 
public  utilities  under  commission  control  such  contract  provisions 
may  not  be  as  essential. 

In  the  following  discussion,  the  rules  and  regulations  in  more 
general  use  are  given  in  considerable  detail.  From  these  rules 
a  selection  of  those  desirable  for  any  given  system  may  be  made, 
the  rule  itself  being  drawn  to  meet  the  local  needs.  No  one 
system  will  require  rules  on  all  the  points  given  and  some  systems 
may  require  special  regulations  in  addition  to  those  mentioned. 

In  the  appendix  the  complete  rules  and  regulations  of  four 
typical  systems  are  given.  The  rules  of  the  Idaho  irrigation 
district  are  brief,  the  addition  of  the  reasons  making  each  rule 
necessary  being  somewhat  novel  but  effective.  Such  rules  are 
suited  to  those  systems  operating  under  relatively  simple  condi- 
tions. The  rules  of  the  Turlock  irrigation  district  are  also  brief. 
They  are  suitable  for  a  system  using  rotation  delivery  with  large 
delivery  heads  and  water  supplies  which  become  less  than  the 
demand  during  the  later  season.  The  rules  of  the  San  Luis 
Power  &  Water  Co.  are  typical  of  those  used  by  such  companies 
in  the  mountain  States.  The  rules  of  the  Fresno  Canal  &  Irriga- 
tion Co.  represent  the  practice  required  for  utility  companies 
by  the  California  Railroad  Commission. 

Control  of  Canal  System.— A  general  rule  used  by  practically 
all  systems  states  that  all  canals,  structures,  gates  or  other  com- 
pany property  are  under  the  exclusive  control  of  the  canal  com- 
pany and  its  officials  and  that  no  others  are  permitted  to  inter- 
fere with  or  change  any  canals  or  gates.  Others  state  that  no 


RULES  AND  REGULATIONS  175 

gates  shall  be  changed  by  any  one  except  the  ditch  rider.  This 
provision  may  be  inserted  even  where  it  is  the  intention  to  permit 
changes  by  users  under  certain  restrictions  as  having  such  a  rule 
gives  a  basis  for  refusing  permission  to  make  such  changes  to 
those  that  abuse  the  privilege.  In  many  States  it  is  a  misde- 
meanor for  any  one  to  interfere  with  or  change  gates  or  to  take 
water  unlawfully  and  such  statutes  are  frequently  appended  to 
the  rules.  The  complete  control  of  gates  by  the  ditch  rider  is 
necessary  where  canals  are  operated  at  maximum  safe  water 
levels  or  where  closely  controlled  and  uniform  delivery  of  water 
is  attempted.  On  some  systems,  particularly  the  older  ones,  the 
land  owner  may  be  required  to  either  install  or  to  pay  the  cost 
of  installing  his  delivery  gate.  In  such  cases  the  control  of  the 
gate  should  be  specified  as  the  ownership  of  it  by  the  land  owner 
may  exempt  him  from  penalties  for  changing  it.  The  penalties 
for  violation  of  rules  regarding  changing  of  gates  should  be  given. 
Reliance  may  be  placed  on  the  statutory  penalties  of  fine  follow- 
ing prosecution  or  the  canal  company  may  enforce  other  penal- 
ties such  as  the  loss  of  the  next  turn  in  rotation  or  charging  for 
double  the  quantity  of  excess  water  procured.  Prevention  is 
preferable  to  reparation.  The  rules  of  the  companies  given  in 
the  appendix  are  typical.  Many  rules  state  the  practice  of  the 
company  in  regard  to  locking  headgates.  The  following  rule  of 
the  Orchard  Mesa  irrigation  district  in  Colorado  is  representative : 

"From  and  after  this  date,  all  headgates  on  delivery  ditches  shall 
be  forthwith  fitted  with  locks  on  the  installation  thereof,  and  all  head- 
gates  to  such  ditches  now  in  existence  shall  forthwith  be  fitted  with 
locks  so  as  to  aid -the  Board  of  Directors,  its  officers  and  agents,  in 
regulating  the  flow  of  water  therethrough." 

Obstructions  to  canals  may  be  specifically  prohibited.  Such 
rules  include  fences  across  ditches,  gates,  and  bridges  on  private 
roads.  The  following  is  a  typical  rule: 

"No  fences,  bridges,  ditches,  buildings  or  other  obstructions  shall 
be  placed  across  or  upon,  or  along  any  canal,  ditch,  right  of  way  or 
property  of  the  Company  without  first  obtaining  the  written  permission 
of  the  Chief  Engineer  stating  the  time,  conditions  and  other  regulations 
governing  the  same." 

Access  to  Land. — Nearly  all  companies  reserve  the  right  to 
have  access  to  the  land  irrigated  both  for  purposes  of  inspecting 
the  crops,  use  of  water  and  condition  of  farm  ditches  and  also 


176  IRRIGATION  SYSTEMS 

for  the  purpose  of  crossing  or  using  the  land  adjacent  to  the  canal 
in  the  case  of  emergency  repairs.  The  rules  given  in  the  appendix 
and  the  one  which  follows  are  typical: 

"  The  ditch  riders  or  other  agents  of  the  company  shall  have  free  access 
at  all  times  to  lands  irrigated  from  the  canal  system,  for  the  purpose  of 
examining  the  canals  and  the  flow  of  water  therein,  or  for  any  other 
purpose  connected  with  the  distribution  of  water  or  the  operations  of 
the  company." 

Location  of  Gates. — A  rule  covering  the  location  of  delivery 
gates  is  frequently  used.  Such  rules  may  specify  the  conditions, 
if  any,  under  which  more  than  one  delivery  per  farm  may  be 
permitted  or  the  maximum  distance  from  the  farm  at  which 
delivery  may  be  made.  Instead  of  specifying  the  conditions 
under  which  gates  may  be  installed,  it  is  perhaps  preferable  to 
require  permission  for  the  installation  and  secure  such  control 
through  the  granting  of  the  permission  in  each  case  as  may  be 
suited  to  the  particular  conditions.  The  rules  of  the  Turlock 
and  Idaho  irrigation  districts  are  in  point. 

Rights  of  Way. — Various  rules  regarding  the  use  of  canal  rights 
of  way  by  adjacent  land  owners  may  be  used.  The  following 
rules  of  the  Sacramento  Valley  West  Side  Canal  Co.  cover  all 
such  conditions  which  need  to  be  met: 

"No  trees,  vines  or  alfalfa  shall  be  planted  on  the, right  of  way  of 
the  irrigating  system  controlled  by  the  Receiver,  and  all  such  growing 
on  such  rights  of  way  shall  belong  absolutely  to  the  utility.  Permis- 
sion, however,  may  be  granted  by  the  Receiver,  under  such  restrictions 
as  may  be  deemed  expedient,  to  raise  annual  crops  thereon,  or  to  use 
such  rights  of  way  for  other  purposes. 

"When  any  right  of  way  is  plowed  or  cultivated  for  any  purpose  the 
furrows  shall  always  be  turned  or  thrown  toward  the  embankment. 

"No  cattle,  horses  or  hogs  will  be  allowed  to  graze  upon  the  right  of 
way  of  any  canal  operated  by  the  Receiver,  but  an  irrigator  may,  upon 
proper  application  being  made  to  the  Superintendent  and  approved 
by  him,  fence  the  right  of  way  of  any  canal  crossing  his  land  and  may 
have  free  use  of  the  same  for  the  pasturing  of  sheep  or  goats. 

"No  fences  or  other  obstructions  shall  be  placed  across,  or  upon,  or 
along  any  canal  bank  or  right  of  way  of  any  canal  or  ditch  operated 
by  the  Receiver  without  his  special  permission.  Whenever  such  special 
permission  shall  be  granted  it  shall  always  be  with  the  distinct  under- 
standing that  proper  openings  or  passageways  for  teams  shall  be  pro- 
vided, and  that  such  fence  or  obstruction  must  be  removed  whenever 
requested  by  the  Superintendent. 


RULES  AND  REGULATIONS  177 

"Persons  are  prohibited  from  crossing  canals  and  laterals  operated 
by  the  Receiver  with  wagons  or  other  vehicles  which  may  cause  any 
injury  to  the  embankment  of  such  canals,  and  should  a  canal  bank  be 
injured  from  this  cause,  the  cost  of  repairing  the  same  will  be  charged 
to  the  land  owner  through  whose  land  the  injured  portion  of  such  canal 
may  pass. 

"Bridges  may  be  constructed  by  the  land  owner  at  his  own  expense 
across  canals  or  laterals  operated  by  the  Receiver,  under  the  super- 
vision of  the  Receiver's  representative,  upon  proper  application  being 
made  and  approved.  Such  bridges  shall  be  maintained  by  and  at  the 
expense  of  the  land  owner.  Should  the  flow  of  water  in  a  company 
lateral  be  obstructed  or  retarded  by  a  bridge  constructed  by  a  land 
owner,  such  bridge  shall  be  removed  by  order  of  the  Receiver,  or  the 
Receiver  may  remove  the  same  at  the  expense  of  said  land  owner." 

Maintenance  of  Laterals. — Where  water  is  delivered  to  the 
heads  of  laterals  only,  a  rule  permitting  the  main-canal  company 
to  refuse  to  make  delivery  to  any  lateral  not  in  proper  condition 
is  usual.  Similar  rules  applying  to  farm  ditches  are  also  fre- 
quently used  where  delivery  is  made  to  individuals.  The  rules 
for  the  four  systems  given  in  the  appendix  are  typical.  The  rule 
on  the  Fresno  Canal  &  Irrigation  Co.'s  system  is  suitable  for 
those  systems  where  the  operation  of  the  laterals  is  being  gradu- 
ally taken  over  by  the  main  system.  On  some  cooperative 
systems  the  land  owners  under  each  lateral  may  maintain  it 
although  delivery  is  made  to  individuals  by  the  main-canal  organ- 
ization. A  similar  rule  requiring  the  lateral  to  be  in  good  condi- 
tion before  water  will  be  turned  into  it  is  necessary  in  order  to 
secure  proper  maintenance  in  such  cases. 

The  following  rules  are  typical  of  those  used  by  different 
systems : 

"Before  water  is  furnished  to  any  private  distributing  ditch  the  land 
owners  receiving  water  therefrom  must  agree  upon  and  sign  rules  and 
regulations  satisfactory  to  the  Board  of  Directors,  providing  for  the 
repair,  maintenance  and  distribution  of  water  from  such  ditch,  author- 
izing some  one  to  represent  the  users  in  all  conferences  with  the  ditch 
tender,  and  providing  for  the  apportionment  of  water,  subject  to  all 
rules  and  regulations  of  the  district."  Modesto  irrigation  district. 

"The  Receiver  will  not  be  liable  for  any  damages  resulting  directly 
or  indirectly  from  the  water  flowing  in  any  private  ditch,  but  the 
responsibility  of  the  Receiver  shall  absolutely  cease  when  the  water 
is  turned  into  the  same.  At  the  beginning  of  the  season,  and  before 
water  will  be  turned  into  any  private  or  party  ditch,  such  ditch  shall 
12 


178  IRRIGATION  SYSTEMS 

be  put  in  good  repair  and  vegetation  shall  be  removed  so  that  water 
may  be  conducted  with  as  little  loss  as  possible.  Such  work  shall 
be  done  to  the  satisfaction  of  the  Superintendent."  Sacramento  Valley 
West  Side  Canal  Co. 

"  If  the  irrigator  desires  to  take  water  through  a  private  ditch  which, 
in  the  opinion  of  the  Zanzero,  is  too  dirty  or  badly  constructed  to  carry 
water  without  unusual  loss,  such  loss  will  have  to  be  borne  by  the 
irrigator;  that  is,  the  water  will  be  measured  before  it  enters  the  ditch." 
Anaheim  Union  Water  Co. 

Delivery  of  Water. — The  rules  governing  delivery  of  water  are 
the  most  important  ones  dealing  with  the  relations  between  the 
irrigators  and  the  canal  organization.  The  character  of  the 
rules  used  for  any  system  depends  on  the  method  of  delivery 
used  and  as  such  methods  vary  widely  the  rules  required  differ 
materially. 

The  rules  of  the  Turlock  irrigation  district  are  suited  to  rota- 
tion delivery  on  a  time  schedule  per  acre.  The  rules  of  the  Fresno 
Canal  and  Irrigation  Co.  are  in  more  detail,  particularly  in 
regard  to  delivery  during  times  of  less  than  full  supply.  More 
detailed  and  specific  rules  are  usually  desirable  in  the  case  of 
commercial  companies  than  for  those  operated  by  the  land 
owners.  The  rule  IX  of  the  Idaho  irrigation  district  is  represen- 
tative of  the  greater  simplicity  possible  for  continuous-flow 
delivery. 

The  rule  of  the  Coneland  Water  Co.  is  to  the  point: 

"Water  will  not  be  delivered  in  continuous  run,  but  will  be  delivered 
in  heads  as  large  as  the  water  user  can  handle,  in  no  case  less  than  40 
miner's  inches;  the  time  of  use  being  reduced  in  proportion  to  the  head 
delivered.  Water  in  excess  of  the  contract  amount  will  not  be  delivered." 

A  clear  explanation  of  the  method  of  delivery  is  given  in  the 
following  rules  of  the  Sacramento  Valley  West  Side  Canal  Co.: 

"For  convenience  and  in  order  to  facilitate  the  distribution  of  water, 
the  lands  under  the  canal  system  are  divided  into  lateral  districts. 

"Each  lateral  district  is  divided  into  rotation  sections,  each  section 
comprising  as  many  irrigators  as  can  be  served  by  one  irrigating  head. 
Rotation  sections  may  be  changed  by  the  Superintendent  from  time 
to  time  in  accordance  with  the  increase  or  decrease  of  the  acreage  of 
land  under  irrigation. 

"The  water  will  be  apportioned  to  each  lateral  district  and  in  case 
of  shortage  in  the  supply  the  apportionment  shall  be  made  in  accordance 
with  the  acreage  actually  being  irrigated  in  each  district. 


RULES  AND  REGULATIONS  179 

"Water  will  be  furnished  in  serviceable  heads  in  turn  or  rotation  to 
each  consumer  in  a  rotation  section,  except  that  when  agreeable  to  the 
Superintendent,  consumers  within  a  rotation  section  may  exchange 
turns  for  mutual  accommodation,  provided  such  exchange  will  not 
alter  the  schedule  of  rotation  for  other  consumers. 

"The  Superintendent  will  give  notice  of  the  beginning  and  duration 
of  each  run  of  water  as  far  in  advance  as  possible,  and  will  notify 
each  consumer  in  advance  when  the  water  will  be  available  to  him  dur- 
ing each  run,  and  further  notify  him  of  any  change  in  the  time  of  de- 
livery. A  consumer  who  fails,  through  his  own  fault,  to  use  his  allot- 
ment or  irrigation  head  during  any  rotation  period  will  not  be  entitled 
to  any  extra  allotment  during  a  later  rotation  period. 

"Each  consumer  will  be  allowed  not  to  exceed  6  acre-inches  for  each 
acre  under  irrigation  during  any  rotation  period,  for  crops  other  than 
rice.  Water  will  be  furnished  under  serviceable  irrigation  heads,  the 
size  of  which  will  depend  upon  the  character  of  the  crop  and  the  area 
of  the  land  under  irrigation  of  each  irrigator. 

"The  time  of  use  shall  begin  when  the  gate  is  opened,  turning  water 
from  the  canals  or  laterals  operated  by  the  Receiver  into  the  farm  ditches 
of  the  consumers,  and  water  must  be  used  continuously  night  and  day 
until  the  quantity  has  been  delivered. 

"Water  will  be  furnished  for  rice  lands  under  such  heads  and  for  such 
periods  as  may  be  required  for  proper  irrigation  of  this  crop  up  to  the 
full  amount  applied  for." 

The  following  rules  apply  to  rotation  delivery  among  small 
holdings  such  as  in  orchard  areas: 

"It  shall  be  the  duty  of  the  distributing  Zanzero  to  deliver  water  in 
regular  runs  beginning  with  the  lower  ditches,  and  deliver  up  in  regular 
order.  In  case  there  is  a  surplus  of  water,  the  Zanzeros  may  suspend 
the  run  by  direction  from  the  Ditch  Committee,  which,  however,  must 
be  resumed  as  soon  as  the  surplus  ceases.  The  Ditch  Committee  shall 
determine  the  order  in  which  the  main  distributing  ditches  shall  be 
served.  The  Zanzero  may  pass  an  irrigator,  who  is  unavoidably  pre- 
vented from  taking  water  in  his  turn,  and  afterward  return  to  him, 
when  this  can  be  done  without  injury  to  the  interests  of  the  company. 

"The  Zanzero  is  to  give  the  irrigator  24  hours  notice  of  the  delivery 
of  water. 

"It  shall  be  the  Zanzero's  duty  to  see  that  water  arrives,  and  con- 
tinues to  flow  to  the  land  being  irrigated  (as  per  notice  previously 
given)  in  as  uniform  stream  as  possible. 

"A  less  head  than  50  inches  shall  not  be  delivered,  except  when  the 
irrigator  is  willing  to  accept  his  measurement  at  the  main  distributing 
ditch.  In  such  cases  any  head  down  to  25  inches  may  be  delivered." 


180  IRRIGATION  SYSTEMS 

A  rule  used  by  a  Colorado  system  is  as  follows: 

"The  periods  of  rotating  water  delivery  to  all  persons  shall  be  charged 
against  them  by  day  and  night,  and  no  extension  of  time  will  be  granted 
to  any  person  by  reason  of  the  fact  that  he  does  not  wish  his  water 
delivered  in  the  night  time." 

Application  for  Water. — The  methods  used  for  handling  appli- 
cations for  water  differ  widely.  For  delivery  under  continuous 
flow  no  application  may  be  used.  The  same  may  be  true  for 
fixed  schedule  rotations.  For  irregular  rotation  on  demand, 
an  application  is  needed.  The  rules  governing  such  applications 
generally  specify  the  form  of  application,  the  place  or  officer  to 
which  the  application  is  made,  and  the  period  of  notice  required 
in  advance  of  delivery.  In  some  cases  seasonal  applications  are 
required.  These  are  needed  to  secure  the  acreages  of  different 
crops  in  planning  rotation  schedules.  Commercial  companies 
require  such  advance  applications  in  order  to  secure  themselves 
for  the  payment  of  charges. 

The  rule  of  the  Turlock  irrigation  district  applies  where  the 
acreage  is  required. in  planning  rotation  schedules.  Rule  3  of 
the  San  Luis  Power  &  Water  Co.  is  suited  to  delivery  on  demand 
controlled  by  a  maximum  amount  of  use.  The  last  portion  of 
this  rule  will  be  of  material  assistance  in  operation,  particularly 
during  the  earlier  years  of  a  system  when  the  irrigated  areas  may 
be  scattered. 

A  rule  used  by  one  public  utility  company  is  as  follows: 

"Parties  requiring  water  for  irrigation  must  make  application  therefor 
in  writing  to  the  company's  canal  superintendent  at  least  ten  (10)  days 
before  the  water  is  needed,  designating  particularly  the  land  and  number 
of  acres  for  which  water  is  required.  Payment  for  the  water  applied 
for  must  be  made  in  advance  at  the  time  of  application." 

The  period  of  notice  required  in  this  rule  is  longer  than  that 
usually  specified.  Three  days  notice  is  typical.  Such  periods 
represent  the  maximum  with  most  systems;  if  3  days  notice  is 
required,  the  company  may  delay  delivery  for  this  period  but 
usually  endeavors  to  comply  with  the  request  in  a  shorter  time. 

The  rule  of  the  Idaho  irrigation  district  given  in  the  appendix 
is  suitable  for  continuous-flow  system.  The  need  for  such  a 
regulation  is  also  tersely  expressed. 

Seasonal  applications  for  commercial  companies  usually  in- 
clude the  area  to  be  irrigated,  its  location,  the  character  of  crop 


RULES  AND  REGULATIONS  181 

and  in  some  cases  an  estimate  of  the  amount  of  water  which  it 
is  expected  will  be  used.  Such  applications  are  generally  re- 
quired by  some  date  in  advance  of  the  operation  season  if  service 
for  that  year  is  to  be  secured.  Arrangements  for  the  payment 
of  charges  must  usually  be  made  at  this  time.  In  case  of  a 
shortage  in  the  supply,  preference  may  be  given  in  order  of 
application.  In  cases  where  such  application  was  not  made 
and  service  is  later  desired,  the  following  rule  is  used  by  one 
company: 

"If  such  application  has  not  been  made  according  to  this  rule,  the 
irrigator  must  make  application  in  writing  to  the  Chief  Engineer  at 
least  10  days  before  the  time  irrigation  is  desired,  and  such  irrigator 
shall  only  be  alloted  water  as  is  consistent  with  the  deliveries  arranged 
for  by  the  Company  under  applications  theretofore  made." 

Where  land  is  rented  an  authorization  must  be  filed  by  the 
owner  to  enable  the  tenant  to  make  application  for  water. 

Minimum  Period  of  Delivery. — Where  water  is  delivered  on 
demand  some  limit  to  both  the  minimum  time  of  delivery  and 
the  minimum  quantity  are  needed  and  a  rule  specifying  such 
limits  is  frequently  used.  The  usual  limit  of  time  is  24  hours ;  the 
limit  of  quantity  for  irrigation  ^  second-foot,  except  on  systems 
supplying  orchards.  Smaller  quantities  may  be  delivered  for 
stock  use.  For  such  small  quantities  a  minimum  charge  per 
delivery  which  is  at  a  higher  rate  than  that  charged  for  average 
conditions  is  usual. 

"This  company  will  not  deliver  water  for  a  shorter  period  than  24 
hours,  nor  for  a  less  amount  than  y±  second-foot,  12>£  inches,  except 
stock  water,  and  the  minimum  charge  of  25  cents  will  be  made  when 
the  amount  does  not  exceed  ^  acre-foot."  Imperial  Water  Co.  No.  1. 

Measurement  of  Water. — Rules  regarding  measurement  of 
water  cover  the  location  of  the  point  of  measurement,  the  char- 
acter of  the  devices  to  be  used,  the  records  to  be  kept  and  the 
furnishing  to  the  land  owner  of  statements  covering  the  amount 
of  water  he  has  received.  In  addition  a  number  of  systems 
print  with  their  rules,  principally  for  the  use  of  ditch  riders, 
tables  for  the  discharge  of  various  devices  in  use  on  the  systems 
and  instructions  for  making  measurements  and  computing  the 
result.  The  rule  of  the  Fresno  Canal  and  Irrigation  Co.  given 
in  the  appendix  is  typical  of  those  suitable  for  a  system  deliver- 
ing mainly  to  laterals  rather  than  to  individuals.  On  systems 


182  IRRIGATION  SYSTEMS 

using  flat  acreage  or  stock  assessment  rates,  measurement  is 
not  usual  and  rules  regarding  it  are  not  needed.  Some  rule 
requiring  the  user  to  sign  a  receipt  for  delivery  is,  however,  fre- 
quently used  on  systems  delivering  on  rotation.  Such  receipts 
are  evidence  that  water  was  delivered  and  where  fairly  uniform 
heads  are  used,  the  time  during  which  water  is  given  to  any  farm 
is  a  rough  measure  of  the  quantity  received. 

Apportionment  in  Time  of  Shortage. — In  case  of  actual  de- 
ficiency in  supply  some  regulation  regarding  the  division  of 
such  supply  is  needed.  On  many  systems  the  late  season  supply 
may  be  less  than  the  demand  in  all  years,  in  others  such  shortage 
may  occur  only  in  years  of  less  than  normal  runoff.  The  avail- 
able supply  may  be  prorated  or  the  preference  given  to  certain 
crops.  The  rules  of  the  Fresno  Canal  and  Irrigation  Co.  are 
quite  complete  and  drawn  to  prevent  discrimination  between 
users  under  this  commercial  company.  Prorating  when  used 
may  be  based  on  the  irrigated  area  for  the  year  .or  on  the  basis 
of  the  amount  of  canal  stock  or  shares  held.  Some  companies 
give  the  canal  officers  authority  to  enforce  rotation  during  periods 
of  shortage  where  continuous  flow  or  delivery  on  demand  may 
be  used  at  other  times.  Such  rotation  may  extend  to  the  parts 
of  the  canal  system  as  well  as  to  individuals. 

The  following  rule  of  the  Modesto  irrigation  district  gives 
preference  on  the  basis  of  the  kind  of  crops: 

"In  case  of  shortage  in  water  priority  will  be  given  first  to  garden 
crops;  second,  to  first-year  trees,  vines  and  cuttings  so  far  as  such  water 
may  be  necessary  to  keep  such  trees  and  vines  alive." 

Interruptions  in  Service. — When  delivery  is  made  in  rotation 
or  on  demand  some  method  of  adjustment  of  delivery  schedule 
is  required  when  service  is  interrupted  due  to  canal  breaks  or 
other  causes.  The  rule  of  the  Turlock  system  is  typical;  for 
breaks  on  the  individual  delivery  ditch  the  water  is  placed  to 
the  next  irrigator  in  order;  for  breaks  on  the  lateral  the  schedule 
is  adv.anced  for  the  time  lost. 

Stock  Water. — Where  water  is  not  delivered  continuously 
some  arrangement  for  the  delivery  of  small  streams  for  stock 
use  during  the  regular  irrigation  season  may  be  required.  Such 
deliveries  may  in  some  cases  also  require  winter  operation  of  the 
system.  In  some  cases  extra  charges  may  be  made  for  such 
service  at  a  certain  rate  per  head  for  various  kinds  of  stock  or 
at  a  fixed  charge  per  delivery. 


RULES  AND  REGULATIONS  183 

"Upon  written  request,  the  superintendent  may  permit  pipes,  where 
a  check  is  not  required,  not  to  exceed  2  inches  in  diameter,  to  be  placed 
in  the  banks  of  the  canal  for  the  purpose  of  drawing  water  for  stock 
and  domestic  use,  and  a  minimum  charge  of  $6  per  year  per  pipe  will 
be  charged,  payable  in  advance  by  all  stockholders  so  served."  Imperial 
Water  Co.  No.  1. 

Waste. — A  rule  giving  the  canal  company  the  right  to  shut  off 
water  which  is  being  wasted  is  usual.  This  is  necessary  if  the 
supply  does  not  exceed  the  needs. 

Rule  III  of  the  Idaho  irrigation  district  given  in  the  appendix 
covers  the  wasting  of  water  into  lower  canals. 

The  following  rule  used  by  one  of  the  California  irrigation 
districts  covers  this  matter  in  detail: 

"Persons  wasting  water  on  roads  or  vacant  land,  or  land  previously 
irrigated,  either  wilfully,  carelessly,  or  on  account  of  defective  ditches 
or  inadequately  prepared  land,  or  who  shall  flood  certain  portions  of 
the  land  to  an  unreasonable  depth  or  amount  in  order  to  properly  irri- 
.gate  other  portions,  will  be  refused  the  use  of  water  until  such  conditions 
are  remedied." 

Terms  of  Payment. — The  terms  of  payment  both  as  to  amount 
and  time,  are  particularly  important  in  the  case  of  commercial 
companies.  Questions  of  assessments  and  payment  are  more 
usually  covered  in  the  by-laws  of  cooperative  systems. 

The  rules  of  one  commercial  system  having  both  a  flat  acreage 
and  a  quantity  rate  are  as  follows: 

"Cash  or  certified  check  covering  10  per  cent,  of  the  estimated 
total  charge  for  the  season  based  on  the  rates  established  must  accom- 
pany each  application.  The  balance  to  be  paid  in  five  equal  monthly 
installments;  such  payments  may  be  evidenced  by  promissory  notes, 
dated  the  first  day  of  each  month,  beginning  May  1,  1916,  all  payable 
Nov.  1,  1916.  Such  notes  to  be  secured  by  a  crop  mortgage  which  shall 
be  a  first  lien  on  the  crop,  or  in  case  such  crop  mortgage  cannot  be 
given,  then  other  security  shall  be  given  to  the  satisfaction  of  the 
Receiver.  Notes  to  bear  interest  at  the  rate  of  7  per  cent,  per  annum. 

"The  Receiver  will  discontinue  the  service  of  water  to  consumers 
during  such  time  as  the  above  terms  are  not  complied  with. 

"In  case  of  measured  service  the  application  must  be  accompanied 
by  cash  or  certified  check  for  20  cents  per  acre  for  agricultural  crops 
and  70  cents  per  acre  for  rice  crops,  and  notes  shall  be  given  for  balance 
to  be  paid  on  the  basis  of  flat  rates.  Before  any  water  is  delivered 
in  excess  of  the  amount  the  consumer  is  entitled  to  by  the  payments 


184  IRRIGATION  SYSTEMS 

made  and  notes  given,  he  shall  give  a  promissory  note,  secured  as 
above,  for  the  additional  amount  estimated  to  be  delivered.  Should 
the  amount  of  water  delivered  as  determined  at  the  end  of  the  season 
be  less  than  that  to  which  the  consumer  is  entitled  by  payments  made 
and  notes  given,  a  rebate  will  be  made  to  him  covering  the  difference." 

The  following  rule  is  used  by  the  Imperial  Water  Co.  No.  1, 
a  cooperative  system  using  a  quantity  rate: 

"All  water  accounts  are  due  on  the  first  day  of  each  month.  Any 
user  of  water  who  has  not  paid  by  the  15th  of  the  month  for  water  used 
for  the  preceding  month  will  be  placed  on  the  delinquent  list.  His 
delivery  box  will  be  locked  by  the  Zanzero  in  charge  and  no  water 
will  be  delivered  to  him  until  such  delinquent  charges  have  been  paid.'* 

The  greater  number  of  cooperative  companies  levy  assessments 
against  the  stock,  the  stock  being  sold  when  delinquent.  As 
delivery  is  based  on  the  ownership  of  stock,  no  operating  rule 
regarding  delinquencies  is  required.  For  irrigation  districts  the 
charges  are  generally  levied  as  taxes  against  the  land  and  the 
district  handles  delinquencies  through  tax-sale  methods  rather 
than  by  refusing  delivery.  The  Oakdale  irrigation  district  in 
California  has  a  rule,  however,  that  no  water  shall  be  furnished 
until  the  charges  for  the  preceding  year  have  been  paid.  The 
right  of  commercial  companies  to  refuse  delivery  due  to  non- 
payment of  previous  charges  involves  many  legal  points,  so  that 
such  rules  may  not  always  be  enforceable. 

Complaints. — Some  rule  defining  a  regular  procedure  for  han- 
dling complaints  is  desirable.  The  general  subject  of  complaints 
is  discussed  on  page  218.  Requiring  the  complaints  to  be  in 
writing  and  to  be  presented  within  from  10  to  15  days  of  the 
occurrence  of  the  cause  are  usual  rules.  The  following  rules  are 
typical: 

"Any  claims  for  shortage  or  irregularity  in  any  run  must  be  made 
in  writing  to  the  superintendent  of  this  company  within  5  days  from 
the  completion  of  the  run. 

"Complaint  from  the  decision  of  the  Zanzero  should  be  made  to  the 
superintendent;  from  the  action  of  the  superintendent,  appeals  may  be 
made  to  the  board  of  directors."  Imperial  Water  Company  No.  1. 

"No  complaint  will  be  considered  by  the  Receiver  unless  made  in 
writing  and  filed  with  him  within  10  days  of  the  time  the  acts  com- 
plained of  have  occurred. 

"Appeals  may  be  made  from  decisions  of  ditch  tenders  to  the  Super- 


RULES  AND  REGULATIONS  185 

intcndent;  from  the  action  of  the  Superintendent  appeal  may  be  made 
to  the  Receiver  of  the  company. 

"Any  complaint  regarding  service  or  application  of  rates  may  be 
referred  to  the  California  Railroad  Commission."  Sacramento  Valley 
West  Side  Canal  Co. 

Liability  of  Company. — Rules  defining  the  extent  of  liability, 
or  what  is  more  often  the  lack  of  liability,  for  damage  caused 
by  water  after  its  delivery  from  the  canal;  for  failure  to  deliver 
due  to  breaks  or  deficient  water  supply;  and  for  such  other  points 
as  local  conditions  may  require,  are  frequently  used.  The  re- 
sponsibility for  a  failure  of  the  water  supply  itself  is  usually 
defined  in  the  water-right  contract  of  commercial  companies 
rather  than  in  the  rules.  For  cooperative  companies  available 
supplies  are  divided  under  rules  discussed  under  apportionment 
in  periods  of  scarcity. 

The  rules  of  the  Turlock  irrigation  district  and  the  San  Luis 
Power  &  Water  Co.,  given  in  the  appendix,  are  typical.  Other 
rules  are: 

"As  the  company  has  no  control  over  ditches  constructed  by 
farmers  and  land  owners  on  their  property,  or  of  the  water  after  it  has 
left  the  discharge  gates  in  the  canal,  the  company  will  not  be  responsible 
for  any  damage  accruing  from  waste  or  overflow  over  public  roads  or 
the  lands  or  crops  of  others,  and  the  takers  of  water  alone  are  liable  for 
such  damage."  San  Joaquin  &  Kings  River  Canal  &  Irrigation  Co. 

"The  Coneland  Water  Co.  will  hot  be  responsible  or  liable  for  any 
damages  resulting  directly  or  indirectly  from  the  overflow  of  water  on 
adjoining  lands  unless  the  same  is  caused  by  neglect  on  the  part  of 
the  company." 

Liability  of  Irrigator. — A  statement  of  the  liability  of  the 
irrigator  for  acts  which  may  result  in  injury  to  the  canal  system 
is  desirable.  The  extent  of  such  liability  or  the  injuries  to  be 
avoided  differ  on  different  systems.  The  following  rules  are 
typical : 

"All  water  users  will  be  held  to  a  strict  accountability  for  damage 
to  company  canals  caused  by  their  turning  a  head  of  water  being  de- 
livered to  them  back  into  the  company  canals.  No  one  except  the 
Zanzero  has  any  authority  to  turn  water  into  or  out  of  the  company's 
canals."  Imperial  Water  Co.  No.  1. 

"Each  water  user  will  be  responsible  for  all  damages  caused  by  his 
wilful  neglect  or  careless  acts  to  the  property  of  the  Company  or  others 
and  upon  his  failure  to  repair  such  damage,  after  notification  by  the 


186  IRRIGATION  SYSTEMS 

Company  or  its  representatives,  such  repairs  will  be  made  by  the 
Company,  at  the  irrigator's  expense,  and  the  water  will  be  shut  off  until 
payment  is  made."  Coneland  Water  Co. 

Penalty  for  Breaking  Rules. — In  order  to  secure  the  enforce- 
ment of  rules,  penalties  for  their  violation  are  required.  Such 
penalties  are  usually  either  a  loss  of  water  or  an  excess  charge. 

"Refusal  to  comply  with  the  requirements  hereof,  or  transgression 
of  any  of  the  foregoing  rules  and  regulations,  or  any  interference  with 
the  discharge  of  the  duties  of  any  official,  shall  be  sufficient  cause  for 
shutting  off  the  water,  and  water  will  not  again  be  furnished  until 
full  compliance  has  been  made  with  all  requirements  herein  set  forth." 
South  San  Joaquin  irrigation  district. 

"Any  violations  of  the  law  or  the  foregoing  rules  must  be  reported  by 
the  Zanzero  to  this  office.  The  company  reserves  the  right  for  any 
violations  thereof  to  cease  supplying  water  to  the  person  so  offending 
until  satisfaction  is  made."  Fairview  Land  &  Water  Co. 

Miscellaneous  Rules. — Various  miscellaneous  rules  may  be 
required  by  local  conditions.  Where  the  water  is  used  for 
domestic  or  stock  purposes,  a  rule  against  pollution  may  be 
needed.  Such  rules  prohibit  allowing  any  refuse,  manure,  dead 
animals  or  other  offensive  material  to  get  into  the  canals. 

A  rule  permitting  modification  of  the  general  rules  for  emer- 
gencies or  special  conditions  may  be  used.  This  is  not  generally 
desirable  as  the  right  of  the  officials  to  make  such  modifications 
is  generally  understood  and  to  specifically  call  attention  to  it 
may  serve  to  weaken  the  force  of  the  other  rules. 


CHAPTER  VII 

PAYMENT  FOR  CONSTRUCTION  AND  OPERATION 
CHARGES 

The  charges  against  the  lands  under  an  irrigation  project  are 
of  two  kinds:  those  for  the  cost  of  construction  of  the  system, 
and  those  for  its  operation.  Both  of  these  charges  must  be  met 
by  the  lands  irrigated  either  directly  by  repayment,  or  as  under 
some  public  utility  systems,  by  the  payment  of  interest  on  the 
construction  cost.  The  methods  of  distributing  these  two 
kinds  of  charges  and  the  terms  of  payment  differ,  so  that  they 
can  be  discussed  separately. 

CONSTRUCTION  CHARGES 

The  construction  or  building  charge  covers  the  cost  of  the  con- 
struction of  the  canal  system  and  is  only  paid  once ;  the  payment 
usually  extending  over  a  period  of  years.  Usual  improvements 
are  generally  classed  with  maintenance  or  betterment  work. 
Supplemental  work,  such  as  the  provision  of  storage  or  extensive 
betterments,  may  be  handled  in  some  cases  in  the  same  way  as 
the  original  construction  work  and  its  payment  extended  over 
several  years. 

With  systems  constructed  by  the  land  owners  the  construction 
charge  is  equal  to  the  actual  cost  of  building  the  system.  This 
applies  to  cooperative  companies  and  to  irrigation  districts 
which  carry  out  the  original  construction  themselves  instead  of 
purchasing  systems  already  built  by  other  forms  of  organization. 
In  the  past  such  forms  of  organization  constructing  systems  for 
their  own  use  without  profit  have  been  in  the  majority,  both  in 
actual  numbers  and  also  in  total  extent  of  area  covered.  At 
present  the  new  developments  in  large  units  are  being  made 
more  largely  by  other  forms  of  organization  which  eventually 
plan  to  transfer  the  control  of  the  system  to  the  control  of  the 
users.  The  construction  charge  may  include  a  profit,  as  in  Carey 
Act  projects  or  systems  constructed  by  private  corporations 

187 


188  IRRIGATION  SYSTEMS 

where  the  cost  of  construction  is  less  than  the  price  received. 
It  may,  and  in  some  cases  has,  included  a  loss  where  the  cost  of 
construction  or  the  time  required  for  settlement  has  exceeded 
the  estimates. 

Apportionment  of  Construction  Costs. — There  are  two  general 
methods  by  which  the  total  construction  charge  may  be  dis- 
tributed to  the  irrigable  land:  one  being  at  a  uniform  rate  per 
acre  of  irrigable  land;  the  other  on  the  basis  of  the  benefits  re- 
ceived or  at  a  variable  rate  per  acre; 

The  uniform  rate  per  acre  method  is  the  more  usual.  It  has 
the  advantage  of  simplicity  in  application.  On  any  given  sys- 
tem the  actual  cost  of  construction  for  the  different  parts  of  the 
system  naturally  varies;  the  head  works  and  diversion  canals  are 
common  to  all  the  lands,  the  cost  per  acre  of  the  distribution 
system  will  vary  with  the  topographic  conditions.  Lands 
nearer  the  upper  portions  of  the  projects  may  be  served  at  a  low 
cost.  It  would  not  be  practicable  to  fix  the  charges  on  the  actual 
cost  of  construction  to  each  area,  as  those  lands  most  difficult 
to  reach  might  require  a  charge  in  excess  of  the  benefit  received. 
A  difference  in  construction  charge  is  sometimes  made  between 
distinct  units  of  large  systems  which  have  been  constructed  at 
different  times  or  at  different  actual  costs.  There  are  other 
systems  where  the  actual  cost  of  construction  between  different 
portions  of  the  project  may  vary  to  a  considerable  extent  and 
yet  a  uniform  charge  be  made  to  all  lands.  This  is  the  case  in 
some  pumping  systems  where  more  than  one  lift  is  used. 

Effect  of  Form  of  Organization. — The  construction  charge  may 
be  assessed  directly  or  indirectly  against  the  lands.  In  coopera- 
tive organizations,  such  as  mutual  or  stock  companies,  the  charges 
are  assessed  against  the  stock  rather  than  directly  against  the 
land.  However,  the  owners  of  the  stock  are  the  owners  of  the 
land,  the  stock  being  held  in  proportion  to  the  irrigable  area 
owned,  such  as  in  companies  issuing  stock,  one  share  of  which 
entitles  the  owner  to  water  for  1  acre  of  land.  This  is  essentially 
a  uniform  rate  per  acre  basis,  although  in  some  cases  one  owning 
land  with  porous  soil  or  otherwise  requiring  excess  amounts  of 
water  might  also  own  or  rent  excess  stock. 

On  Carey  Act  projects  the  construction  charge  is  fixed  by  con- 
tract between  the  State  and  the  constructing  company.  This 
has  generally  been  on  a  uniform  rate  per  acre  basis.  In  some 
States  the  rate  fixed  is  the  maximum  which  can  be  charged  by 


CONSTRUCTION  AND  OPERATION  CHARGES       189 

the  company.  This  enables  the  constructing  company  which 
also  handles  the  colonization  to  reduce  the  price  on  the  poorer 
lands  if  desired.  Such  differences  in  price  that  may  be  made  are 
due  to  differences  in  the  value  of  the  lands,  such  as  roughness, 
poorer  soil  or  other  factors  rather  than  to  a  variation  in  the  price 
of  the  water  right.  Such  a  method  would  represent  an  approxi- 
mate charge  on  the  basis  of  benefit.  The  purchasers  of  Carey 
Act  lands  have  generally  paid  uniform  rates  per  acre  for  their 
water  rights,  however.  On  the  projects  of  the  U.  S.  Reclamation 
Service,  the  construction  charges  are  made  at  a  uniform  rate  per 
acre  for  each  unit  of  the  different  projects. 

The  irrigation  district  laws  in  Idaho,  Nevada  and  Washington 
require  that  assessments  shall  be  made  on  the  basis  of  the  bene- 
fits to  the  land.  In  California,  Nebraska  and  Texas  an  ad  valo- 
rem basis  must  be  used,  lands  being  assessed  for  their  value,  the 
improvements  being  exempted.  The  other  seven  States  having 
irrigation  district  laws  (Arizona,  Colorado,  Montana,  New 
Mexico,  Oregon,  Utah,  and  Wyoming)  provide  that  all  lands 
shall  be  assessed  at  the  same  rate  per  acre.  In  California  the 
ad  valorem  basis  was  originally  adopted,  due  to  uncertainty  as 
to  the  legality  of  other  methods.  In  practice  the  ad  valorem 
basis  may  be  similar  in  result  to  the  benefit  basis.  It  resembles 
the  flat  rate  per  acre  in  some  districts  where  values  are  based  on 
distance  from  towns  rather  than  water  requirements  or  produc- 
tion. On  systems  built  by  private  companies  the  price  of  the 
combined  land  and  water  may  be  varied  in  different  parts  of  the 
system  or  for  different  individual  farms.  This  variation  is  more 
usually  due  to  differences  in  the  value  of  the  lands,  rather  than 
variations  in  the  construction  charges. 

Comparison  of  Flat  Rate  and  Benefit  Charges. — These  ex- 
amples indicate  that  the  uniform  rate  per  acre  is  the  more  usual 
basis  for  assessing  construction  charges.  This  is  particularly 
true  of  the  smaller  systems  where  the  variation  in  soils  and  topog- 
raphy is  usually  less.  On  the  large  systems  this  method  is  also 
generally  used  except  for  projects  divided  into  separate  units. 
Within  such  large  projects  the  soil  and  topography  naturally 
vary  more  widely  than  on  smaller  systems.  On  the  more  porous 
soils  or  rougher  lands  the  returns  per  acre  from  cultivation  may 
be  less  and  the  cost  of  construction  greater  than  for  the  lands 
having  more  uniform  topography.  In  such  cases  the  basis  of 
benefit  or  value  of  the  water  to  the  land — an  application  of  the 


190  IRRIGATION  SYSTEMS 

principle  of  "what  the  traffic  can  bear" — may  be  necessary, 
rather  than  the  average  cost  of  construction.  When  such  condi- 
tions are  extreme,  it  is  better  to  exclude  such  lands  from  the 
irrigable  area. 

The  adoption  of  a  benefit  basis  for  the  payment  of  construc- 
tion charges  has  been  retarded  by  the  difficulty  of  its  applica- 
tion. The  benefits  are  not  fixed  amounts,  but  change  with 
changing  conditions  of  ground  water  and  other  factors.  Their 
determination  at  the  beginning  of  the  operation  of  any  system 
involves  elements  of  prophesy  as  to  future  conditions  which  render 
the  results  uncertain.  Some  of  the  States  requiring  the  use  of 
the  flat  acreage  rate  for  assessment  in  irrigation  districts  also 
require  a  benefit  basis  for  drainage  districts.  Such  a  basis  can 
be  applied  much  more  easily  to  drainage  districts  as  the  damage 
done  to  the  land  is  a  measure  of  the  benefit  that  will  result  from 
its  drainage. 

The  cost  of  construction  on  the  more  expensive  systems  may 
exceed  the  value  of  the  water  to  some  of  the  poorer  lands  under 
the  system.  The  exclusion  of  such  lands  would  increase  the 
cost  per  acre  of  serving  the  remaining  better  lands,  so  that  it 
may  be  profitable  to  sell  rights  to  the  poorer  lands  at  prices 
somewhat  lower  than  the  average  cost  of  construction.  On 
the  earlier  and  less  expensive  projects,  the  value  of  the  water  to 
all  irrigable  lands  was  generally  greater  than  its  cost.  In  the 
more  expensive  systems  now  being  built  this  may  not  be  the  case 
and  the  uniform  rate  per  acre  basis  of  construction  charge  may 
need  modification  to  fit  these  conditions.  Among  such  methods 
may  be  the  division  of  projects  into  units,  the  lands  within  which 
have  similar  conditions  and  which  are  charged  similar  amounts 
per  acre  or  a  charge  based  on  actual  estimated  benefits  to  each 
tract.  Such  methods  can  be  most  easily  applied  where  the 
organization  fixing  the  construction  charge  also  fixes  the  price 
of  the  land,  as  in  colonization  projects  handled  without  public 
control  or  for  systems  handled  under  irrigation  district  laws  where 
the  method  of  assessment  is  fixed  by  law. 

Up  to  the  present  nearly  all  charges  are  based  on  the  irrigable 
area  with  some  limit  as  to  the  maximum  amount  of  water  which 
will  be  furnished  per  acre.  Charges  per  acre  with  a  specified 
rate  of  supply,  such  as  1  second-foot  to  each  80  acres,  or  a  de- 
livery of  a  certain  maximum  number  of  acre-feet  per  acre  make 
the  area,  rather  than  the  water  used,  the  basis  of  the  charges. 


CONSTRUCTION  AND  OPERATION  CHARGES       191 

Such  rates  of  use  are  usually  sufficient  for  the  more  porous 
soils;  land  requiring  less  than  average  amounts  of  water  secures 
no  advantage  in  the  construction  charge.  On  projects  supplied 
from  storage  where  the  cost  of  construction  consists  more  largely 
of  the  cost  of  storage,  a  construction  charge  based  on  water 
used  would  more  nearly  represent  the  cost  of  service.  Where 
stock  in  cooperative  companies  is  held  in  proportion  to  the 
water  requirements  of  the  lands,  the  construction  cost  is  more 
nearly  based  on  the  water  used  than  on  the  area  of  the  land. 
Where  the  water  available  rather  than  the  amount  of  land  is  the 
limiting  factor  in  development,  a  building  charge  based  on  the 
extent  of  use  without  regard  to  the  area  on  which  it  is  used  may 
be  desirable. 

Classification  of  Irrigable  Area. — Both  construction  and  opera- 
tion charges  are  generally  based  on  the  net  irrigable  area.  In 
some  States  irrigation  districts  assess  against  all  lands  within 
the  district  which  may,  as  in  California,  include  town  lots. 
Provisions,  are,  however,  made  in  all  States  for  excluding  from 
the  districts  lands  which  are  not  physically  irrigable.  The 
classification  of  the  land  in  a  system  becomes  of  importance  in 
many  cases.  In  the  smaller  systems,  more  common  in  the  past 
where  the  cost  per  acre  of  construction  was  usually  less  than  in 
the  systems  now  being  built,  the  total  difference  in  the  charge 
to  any  farm  due  to  minor  classifications  of  the  irrigable  area  were 
not  as  important  and  the  gross  area  was  more  often  used.  With 
the  higher  costs  now  more  usual  on  the  large  systems,  closer 
classification  is  demanded. 

If  the  total  irrigable  area  is  to  bear  the  total  cost,  the  exclu- 
sion of  those  areas  which  affect  all  farms  to  about  the  same  extent 
will  not  materially  affect  the  cost  per  farm.  Such  might  be  the 
case  in  regard  to  roads  which  for  farms  of  about  the  same  size 
will  be  a  small  and  usually  fairly  uniform  proportion  of  each 
farm. 

The  rules  for  the  classification  of  irrigable  land  vary  with  dif- 
ferent systems.  Among  the  methods  used  are  the  following. 
The  areas  as  shown  by  the  U.  S.  Land  Office  plats  are  usually 
accepted  unless  actually  known  to  be  in  error  by  some  minimum 
percentage  or  acreage,  such  as  making  no  correction  of  less  than 
1  acre.  Land  which  is  rocky,  alkali,  seeped,  high,  or  consists 
of  borrow  pits  or  creek  channels  may  be  deducted  if  the  cost, 
of  clearing,  reclaiming  or  levelling  exceeds  some  figure  of  cost 


192  IRRIGATION  SYSTEMS 

approximating  the  value  of  the  land  when  made  irrigable.  Such 
costs  will  vary  widely  with  different  systems  and  localities. 
Land  having  slopes  of  over  10  or  20  per  cent,  may  be  deducted, 
steeper  slopes  being  included  where  the  soil  is  relatively  deep. 
Lands  having  less  than  a  certain  depth  of  soil,  such  as  1  foot, 
over  rock  or  hardpan  may  be  deducted.  The  extent  of  high 
areas  is  determined  by  running  out  grade  contours  from  the 
delivery  box  on  flat  grades  which  for  small  ditches  are  taken 
from  0.05  to  0.10  feet  per  100  feet.  All  deeded  rights  of  way 
such  as  roads,  canals  and  railroads  are  usually  deducted,  rights 
of  way  consisting  of  easements  more  usually  are  not.  Rights 
of  way  for  canals  over  a  certain  capacity  or  width  of  right  of 
way  may  be  deducted  and  smaller  ones  included.  Private 
roads  are  not  deducted.  If  the  total  non-irrigable  land  does 
not  exceed  some  fixed  amount  such  as  1  acre  or  some  percentage 
of  the  total  area,  no  deduction  is  made.  Individual  areas  are 
determined  to  the  nearest  0.2  to  1.0  acres  in  different  systems. 
The  methods  used  vary  on  different  projects,  due  to  differing 
local  conditions.  A  method  relatively  fair  to  different  farms  is 
more  essential  than  one  actually  exact.  The  irrigable  area  on 
any  farm  is  not  a  fixed  quantity.  It  may  gradually  be  increased 
as  land  values  increase  by  the  levelling  of  borrow  pits,  grading 
of  knolls,  etc.  It  may  also  be  decreased  by  new  roads  or  water- 
logging. 

Terms  of  Payment. — The  terms  of  payment  by  the  land  owners 
vary  with  the  form  of  organization.  Where  the  systems  are 
constructed  by  the  organized  owners  of  the  individual  farms,  as 
in  districts  or  cooperative  companies,  the  collective  credit  of 
such  owners  may  be  used  to  finance  construction  and  the  time 
of  payment  extended  over  relatively  long  periods  of  time  by 
means  of  bonds.  Interest  must  be  paid  on  such  funds.  The 
usual  rate  on  the  face  value  of  irrigation  district  bonds  is  6  per 
cent.  The  terms  of  sale  for  such  bonds  have  been  such  in  many 
cases  that  the  actual  rate  has  materially  exceeded  this  rate.  In 
some  States  the  laws  permit  the  payment  of  interest  for  1  or  2 
years  to  be  made  from  the  funds  secured  by  the  bonds  themselves. 
Irrigation  district  bonds  are  issued  for  periods  of  from  20  to  40 
years  and  are  usually  retired  at  a  graduated  rate  during  the 
second  half  of  their  life.  With  cooperative  companies  borrowed 
funds  are  more  usually  secured  on  notes  for  shorter  periods  of 
time.  In  many  cases  the  full  or  a  large  part  of  the  construction 


CONSTRUCTION  AND  OPERATION  CHARGES       193 

cost  is  assessed  directly  to  the  stock  and  the  individual  stock- 
holders required  to  finance  their  own  portion  of  the  cost. 

On  systems  built  for  sale  with  the  lands  the  terms  are  often 
based  upon  the  condition  of  the  land  market  and  resources  of  the 
constructing  company.  The  present  tendency  is  to  make  the 
terms  of  payment  as  liberal  as  the  condition  of  the  constructing 
company  will  permit,  interest  at  usual  rates  being  charged  on 
the  deferred  payments.  Payments  extending  over  periods  of 
from  6  to  15  years,  graduated  in  some  cases,  are  used  by  different 
systems.  The  payment  during  the  first  years  after  purchase 
may  be  made  low,  in  order  to  enable  the  settler  to  use  his  re- 
sources in  improvements  on  the  land. 

The  experience  of  the  U.  S.  Reclamation  Service  has  been  of 
interest  in  this  regard.  The  original  act  provided  that  the 
building  charge  should  be  paid  in  10  equal  annual  installments 
without  interest.  This  was  found  to  be  too  burdensome  for  the 
settlers  on  many  projects  and  in  1914  a  law  was  passed  granting 
a  total  of  20  years  for  the  repayment  of  the  building  charges  on  a 
graduated  scale.  For  new  entries  this  is  to  be  5  per  cent,  at  time 
of  entry,  with  no  further  payments  for  5  years,  5  per  cent,  per 
year  from  the  sixth  to  the  tenth  year,  and  7  per  cent,  per  year 
for  the  remaining  10  years.  As  no  interest  is  charged,  this  is 
equivalent,  at  usual  rates  of  interest,  to  reducing  the  cash  value 
to  the  settler  at  the  time  of  entry  to  about  one-half  the  face  value. 
The  inability  of  settlers  on  many  systems  to  meet  the  annual 
payments  on  the  construction  charge  where  the  period  of  pay- 
ment has  been  made  short  has  led  to  much  agitation  in  favor  of 
some  form  of  rural  credits.  It  is  now  well  recognized  that  much 
capital  is  required  to  develop  an  irrigated  farm.  Either  the 
development  must  be  left  to  those  possessing  such  capital  or  the 
conditions  for  borrowing  must  be  made  favorable  for  those  lack- 
ing in  capital.  On  funds  secured  from  bonds  by  the  land  owners, 
repayment  does  not  usually  begin  for  10  years  or  more.  Where 
land  is  purchased  from  the  constructing  company,  a  first  pay- 
ment is  required.  The  amount  of  this  payment  usually  varies 
from  10  to  25  per  cent,  of  the  total.  It  should  be  equal  to  the 
cost  of  securing  the  purchaser  which  has  been  as  much  as  20 
per  cent,  of  the  price  in  some  cases.  The  tendency  is  toward  a 
smaller  initial  payment  in  order  that  the  settler  may  use  his 
available  funds  more  largely  in  the  development  of  his  land  to  a 
productive  basis. 

13 


194  IRRIGATION  SYSTEMS 

OPERATION  AND  MAINTENANCE  CHARGES 

The  two  general  methods  by  which  operation  and  mainte- 
nance costs  are  charged  to  the  land  are  the  flat  rate  per  acre  and 
the  quantity  rate.  In  the  flat  rate  per  acre  method,  the  charges 
are  based  on  the  area  irrigated  without  regard  to  the  amounts 
of  water  actually  used,  except  as  this  is  limited  to  some  maximum 
quantity  by  the  terms  of  the  water  right.  In  the  quantity  or 
metered  method,  the  charges  are  based  more  or  less  completely 
on  the  amounts  of  water  actually  delivered  to  any  tract  of  land, 
more  usually  the  actual  charge,  however,  consists  of  a  minimum 
charge  per  acre  plus  a  rate  per  acre-foot  for  water  used  in  excess 
of  a  certain  amount.  There  is  much  difference  of  opinion  at 
present  as  to  which  is  the  better  method.  Where  the  policy  of 
the  system  and  methods  of  charging  are  determined  by  others 
than  the  actual  users  of  the  water,  the  quantity  rate  is  frequently 
used;  where  the  users  of  the  water  control  the  system,  the  flat 
rate  per  acre  is  more  usual.  Both  of  these  statements  are,  how- 
ever, subject  to  many  individual  exceptions.  There  are  certain 
conditions  for  which  either  method  is  better  suited  than  the  other; 
there  are  other  conditions  for  which  it  will  be  more  difficult  to 
make  a  choice. 

The  flat  rate  per  acre  is  the  older  method  in  this  country.  It 
is  the  natural  outgrowth  of  the  cooperative  company  where  all 
costs  were  assessed  uniformly  against  the  stock  of  the  company, 
which  was  usually  held  in  proportion  to  the  irrigable  area  of  each 
owner.  It  is  also  the  outgrowth  of  the  earlier  developments 
where  the  water  was  entirely  secured  by  direct  diversion  from 
the  stream  and  the  cost  of  service  was  more  largely  a  question  of 
the  maximum  rate  at  which  water  was  taken  and  the  total  length 
of  season  than  a  question  of  the  actual  amount  of  water  used  per 
acre.  Where  the  area  of  a  project  is  fixed  and  fully  developed 
and  where  the  available  water  supply  is  ample,  a  reduction  in 
the  quantity  used  due  to  a  change  in  the  method  of  charging  may 
have  little  direct  financial  value  to  the  system,  as  it  may  have 
no  other  opportunity  for  using  such  water.  There  is,  however,  a 
direct  public  interest  in  such  reductions  of  the  quantity  used. 
On  systems  supplied  from  storage  or  by  pumping,  the  cost  of 
operation  may  be  determined  more  largely  by  the  amount  of 
water  used  than  by  the  area  covered.  A  more  economical  use 
of  water  on  systems  covering  bench  land  may  enable  the  systems 
to  be  extended  to  cover  additional  areas.  More  economical  use 


CONSTRUCTION  AND  OPERATION  CHARGES       195 

may  be  required  after  the  first  few  years  of  operation,  in  order  to 
furnish  water  for  the  additional  areas  prepared  each  year. 
Better  and  cheaper  methods  of  measuring  the  water  to  individual 
farms  are  being  developed ;  the  damages  to  the  land  from  overuse 
of  water  are  becoming  better  understood  and  more  attention  is 
being  paid  to  better  farm  irrigation  practice. 

Limits  of  Beneficial  Use. — Legal  rights  to  the  use  of  water 
acquired  by  appropriation  are  based  on  the  requirements  of 
beneficial  use.  The  laws  of  several  of  the  States  or  the  rules  of 
the  State  engineer's  office  give  the  maximum  rates  of  use  which 
will  be  considered  beneficial.  In  Wyoming,  Nebraska,  Utah 
and  New  Mexico  this  is  1  second-foot  to  70  acres;  in  Idaho,  1 
second-foot  to  50  acres;  in  Oregon,  1  second-foot  to  80  acres; 
and  in  Nevada,  1  second-foot  to  100  acres  at  the  land.  In 
Wyoming  there  is  no  limit,  other  than  beneficial  use,  to  the 
length  of  the  time  of  use  or  total  quantity  to  be  taken  per  acre  in 
any  year,  except  as  limited  by  the  maximum  rate  of  diversion; 
in  Nebraska  the  total  quantity  is  limited  to  3  acre-feet  per  acre; 
in  Utah  the  total  quantity  is  similarly  limited,  and  the  period 
of  the  year  during  which  the  water  is  to  be  used  must  also  be 
stated;  in  Nevada,  total  use  and  rates  of  use  per  month  are  speci- 
fied. In  Colorado  and  Montana  there  is  no  statutory  limit  to 
the  use  which  will  be  considered  beneficial,  the  determination 
in  each  case  being  left  to  the  courts.  The  States  at  first  followed 
the  Colorado  method;  Wyoming  then  passed  the  laws  limiting  the 
maximum  rate  of  diversion,  and  the  other  States  have  enlarged 
these  statutes  as  outlined  above,  the  law  in  Nevada  being  the 
most  recent  and  also  limiting  the  use  more  nearly  on  a  quan- 
tity basis,  rather  than  a  rate-of-flow  basis.  There  seems  to  be  a 
rather  definite  tendency  in  water-right  regulation  to  more  closely 
restrict  the  maximum  rate  at  which  water  may  be  used  and  also 
to  limit  the  total  amount  per  acre  which  can  be  diverted  per 
season,  or  an  approach  to  determining  the  extent  of  beneficial 
use  in  terms  of  the  quantity  used  per  acre,  rather  than  the  maxi- 
mum rate  of  use. 

Factors  Affecting  Use  of  Water. — The  amount  of  water  used 
on  any  farm  or  under  any  irrigation  system  depends  on  the  soil, 
topography,  ground-water  conditions,  crops,  method  of  prepar- 
ing land  and  care  used  in  applying  water.  These  factors  vary 
on  the  different  parts  of  a  system  or  even  on  adjacent  farms. 
Certain  of  the  factors  are  fixed,  such  as  soils;  others  may  change, 


196  IRRIGATION  SYSTEMS 

such  as  ground-water  conditions  and  crops.  Some  of  the  con- 
ditions of  use  can  be  controlled  by  the  irrigator,  such  as  the  care 
used  in  preparing  land  and  applying  water;  the  fixed  factors  and 
some  of  the  variable  ones,  such  as  changing  ground-water  condi- 
tions caused  by  use  on  higher  areas,  are  not  subject  to  control 
by  the  individual  land  owner.  If  the  variations  in  use  resulted 
only  from  the  factors  under  the  control  of  the  individual  land 
owner,  the  quantity  rate  would  be  preferable,  as  under  such  a 
method  of  charges  those  carelessly  preparing  their  land  or  using 
water  wastefully  would  be  penalized  for  their  neglect  to  the  bene- 
fit of  the  careful  irrigator  whose  charges  would  be  correspondingly 
reduced.  If  the  variations  in  use  result  from  the  factors  which 
the  irrigator  cannot  control,  the  quantity  rate  increases  the  cost 
of  production  on  lands  of  high-water  requirements  and  tends  to 
depreciate  their  value.  That  the  relative  water  requirement  is 
an  actual  element  in  the  value  of  lands  is  coming  to  be  recognized 
although  as  yet  it  is  not  as  important  as  several  other  elements 
of  value  except  for  extreme  soil  types.  The  same  elements  of 
soil  character  which  increase  the  water  requirement  may  increase 
the  cost  of  other  cultivation  operations. 

Effect  of  Rates  on  Measurement  of  Water. — The  use  of  a 
quantity  basis  makes  necessary  the  measurement  of  water  to 
individuals.  The  conditions  of  delivery  on  many  projects  are 
such  as  to  make  accurate  measurements  very  difficult,  and  this 
has  been  one  of  the  principal  reasons  for  retaining  the  flat  rate 
per  acre  method  of  charges.  If  the  cost  to  the  user  depends  on 
the  records  of  water  delivered  to  his  land,  a  more  careful  and 
accurate  measurement  will  be  demanded  than  where  the  users 
interest  is  limited  only  to  securing  water  sufficient  for  his  needs. 
The  cost  of  such  measurement  need  not  be  excessive.  The  gage 
readings  on  which  the  records  are  based  can  usually  be  taken  by 
the  ditch  riders  in  the  course  of  their  other  duties  without  reduc- 
ing the  extent  of  their  beats.  The  computation  of  results  is  an 
added  expense.  The  cost  per  season  of  securing  and  computing 
measurement  records  of  individual  deliveries,  but  not  including 
the  cost  of  installing  and  maintaining  the  measuring  devices, 
should  not  exceed  5  cents  per  acre,  and  for  systems  supplying 
large  farms  with  infrequent  deliveries  may  be  less.  The  interest 
on  the  cost  and  the  depreciation  of  the  measuring  devices  varies 
more  widely.  Costs  of  measurement  are  discussed  in  detail  in 
Chapter  V. 


CONSTRUCTION  AND  OPERATION  CHARGES       197 

FLAT  RATES 

The  adjustment  of  flat  rates  for  operation  and  maintenance  is 
relatively  simple.  Where  the  charges  are  based  on  acreage, 
the  total  charges  divided  by  the  acreage  gives  the  rate  per  acre. 
The  irrigable  area,  determined  as  in  the  case  of  construction 
charges,  is  generally  used.  In  some  cases  the  charges  may  be 
made  only  to  lands  actually  irrigated.  The  assessment  of  opera- 
tion and  maintenance  against  the  irrigable  area  is  preferable  as 
it  tends  to  limit  speculative  land  holdings  and  to  increase  the 
rate  of  development.  Where  the  charges  are  assessed  against 
stock  in  cooperative  companies,  the  basis  is  equivalent  to  assessing 
the  irrigable  area. 

In  some  cases  the  rates  may  be  different  in  different  parts  of 
systems  using  flat  acreage  rates.  Some  cooperative  systems  have 
more  than  one  class  of  stock.  This  may  be  due  to  a  large  area 
cooperating  in  the  construction  of  the  diversion  canal,  storage 
or  other  common  works  with  separate  organizations  handling 
the  distribution  systems  in  the  different  divisions  or  districts. 

QUANTITY  RATES 

Where  the  quantity  basis  of  charges  is  used,  the  rate  generally 
consists  of  two  parts,  the  demand  and  the  service  or  delivery 
charge.  The  demand  or  standby  charge  is  usually  a  fixed  amount 
per  acre  of  irrigated  or  irrigable  land,  the  payment  of  which 
entitles  the  owner  to  a  certain  minimum  amount  of  water  per 
acre,  such  as  1  or  2  acre-feet.  For  water  used  in  excess  of  the 
minimum  a  certain  rate  per  acre-foot  is  charged. 

In  determining  rates  for  different  forms  of  utilities  two  general 
methods  are  used.  In  one,  the  rates  for  different  classes  of 
service  are  made  proportional  to  the  cost  of  supplying  such 
service;  in  the  other,  the  rates  are  adjusted  among  the  different 
classes  of  service  so  as  to  produce  the  desired  total  earning  the 
rates  to  each  class  being  based  on  the  value  of  the  service  rather 
than  its  cost,  a  method  frequently  referred  to  as  charging  "what 
the  traffic  will  bear."  An  irrigation  company  usually  has  only 
one  class  of  service.  These  two  methods  have  their  applica- 
tion in  irrigation,  however,  when  the  rates  are  based  on  the  quan- 
tity of  water  used.  If  the  rates  are  to  be  based  on  the  cost  of 
service,  those  items  of  cost  which  are  not  proportional  to  or 
dependent  upon  the  quantity  of  water  used  should  be  returned 


198  IRRIGATION  SYSTEMS 

by  the  minimum  charge,  and  those  items  which  are  more  nearly 
proportional  to  the  quantity  of  water  used  should  be  returned 
by  the  rate  per  acre-foot  for  quantities  used  in  excess  of  the 
minimum.  If  the  rates  are  to  be  based  on  the  value  of  irrigation 
or  the  benefit  to  the  irrigator,  the  rates  may  be  made  proportional 
to  the  quantity  of  water  used  and  the  service  portion  of  the  rate 
made  to  return  a  large  part  or  all  of  the  total  cost. 

Classification  of  Operation  and  Maintenance  Costs. — The  cost 
of  operation  of  irrigation  systems  can  be  divided  into  four  general 
classes:  (1)  fixed  charges,  (2)  operation,  (3)  maintenance,  (4) 
general  expense.  Each  of  these  is  an  actual  part  of  the  cost  of 
service;  in  many  systems  owned  by  the  users  the  construction 
cost  may  have  been  paid  in  the  original  price  of  the  water  rights 
so  that  interest  charges  are  not  included  in  the  annual  rates. 

If  each  user  has  repaid  his  proportion  of  the  cost  of  construc- 
tion, the  annual  charges  will  consist  of  the  annual  expenditures 
for  operation  and  maintenance.  Depreciation  may  be  met  in 
the  maintenance  as  it  occurs  in  such  cases  instead  of  by  reserves. 
The  annual  rate  for  operation  and  maintenance  can  then  be  based 
on  any  desired  division  of  the  cost  between  acreage  and  the  use 
of  water.  Fixed  charges  are  properly  an  acreage  charge.  Main- 
tenance is  also  dependent  on  acreage  rather  than  on  use  per  acre. 
General  expenses  are  more  largely  an  acreage  cost  than  a  quantity 
cost  although  they  may  be  distributed  to  operation  and  main- 
tenance in  some  cases.  Operation  depends  on  both  acreage 
and  use  and  its  cost  should  be  segregated  to  these  two  divisions 
where  quantity  rates  are  to  be  fixed  on  the  cost  of  service.  Even 
if  the  rates  are  not  based  on  the  cost  of  service  it  is  desirable  to 
know  the  demand  and  service  portions  of  such  costs  if  they  are 
to  be  departed  from  intelligently.  The  cost  of  operation,  such 
as  ditch  riders  and  water  masters,  is  not  entirely  a  delivery  cost. 
If  a  system  is  to  be  operated  at  all  the  cost  of  operation  or  de- 
livery will  not  be  proportional  to  the  water  used.  A  certain 
delivery  organization  will  be  required  in  any  case  and  a  consider- 
able part  of  the  cost  of  such  distribution  force  can  be  considered 
a  demand  charge  rather  than  a  direct  delivery  cost.  The  relative 
use  of  water  may  not  affect  the  construction  cost.  Where  water 
is  secured  from  direct-flow  rights  in  streams,  the  cost  of  con- 
struction is  mainly  controlled  by  the  maximum  rate  or  peak  load 
of  use  which  determines  the  canal  capacities  and  cost  of  con- 
struction. The  service  or  direct  quantity  costs  are  the  cost 


CONSTRUCTION  AND  OPERATION  CHARGES       199 

of  part  of  the  actual  delivery  force  and  the  cost  of  securing  water 
such  as  storage  or  pumping  where  such  occur.  The  cost  of  the 
measurement  of  water  to  individuals  should  be  included  in  the 
delivery  cost. 

Such  an  analysis  places  the  fixed  charges,  maintenances,  general 
expenses  and  a  portion  of  the  operation  costs  in  the  demand 
charge  and  leaves  only  the  cost  of  securing  the  water,  its  distribu- 
tion and  measurement  as  the  direct  delivery  or  service  costs. 
The  actual  and  relative  amounts  of  these  different  items  vary  with 
each  system.  In  all  but  commercial  companies  it  is  not  usual 
to  include  interest  on  the  value  of  the  system  in  the  fixed  charges 
although  other  systems  may  partly  meet  such  charges  through 
interest  payments  on  outstanding  bonds,  which  may,  however, 
be  carried  as  distinct  accounts.  Also,  the  greater  number  of 
systems  at  present  secure  their  supply  by  direct  diversion  so 
that  the  development  cost  for  the  water  itself  such  as  storage  or 
pumping  may  be  relatively  small.  Such  an  analysis  will  usually 
show  a  relatively  small  delivery  cost  per  acre-foot.  Some  general 
figures  on  the  relative  amounts  of  these  different  items  are  given 
in  the  following  discussion. 

Ratio  of  Demand  and  Service  Costs. — In  the  13th  U.  S. 
Census  figures  were  obtained  on  the  average  cost  of  operation 
and  maintenance  for  about  one-half  of  the  area  irrigated.  These 
costs  included  the  majority  of  the  systems  except  those  classed 
as  individual  or  partnership  enterprises.  For  these  two  classes 
operation  and  maintenance  are  handled  incidentally  by  the  users 
without  definite  records  or  charges.  The  average  cost  of  opera- 
tion and  maintenance  for  all  the  States  was  $1.07  per  acre,  vary- 
ing from  $0.63  in  Idaho  to  $3.25  in  Texas.  The  average  cost  of 
construction  per  acre  actually  irrigated  in  1909  for  all  States  was 
$22.41,  the  average  cost  per  acre  which  completed  systems  were 
ready  to  supply  in  1910,  $15.92.  Using  the  latter  figure  as  the 
average  construction  cost  and  assuming  8  per  cent,  for  interest 
and  depreciation,  a  relatively  low  figure  as  the  cost  of  interest 
alone  may  exceed  this  for  newer  systems,  the  fixed  charges 
become  $1.28  per  acre.  The  total  cost  would  then  be  $2.35 
per  acre  of  which  operation  and  maintenance  would  form  only 
45  per  cent.  These  fixed  charges  are  relatively  low  as  the  cost  of 
construction  is  figured  on  the  total  area  irrigable  and  also  in- 
cludes the  construction  cost  of  individual  and  partnership  sys- 
tems which  the  census  found  served  about  40  per  cent,  of  the 


200  IRRIGATION  SYSTEMS 

irrigated  area  and  had  an  average  construction  cost  of  less  than 
one-half  of  the  mean  for  all  systems.  The  average  cost  of  con- 
struction of  the  systems  for  which  operation  and  maintenance 
costs  were  secured  would  exceed  the  figure  used  giving  a  corre- 
spondingly higher  fixed  charge  and  lower  proportionate  expense 
for  operation  and  maintenance. 

As  a  result  of  its  investigations  in  rate  cases,  the  California 
Railroad  Commission  has  determined  the  operating  costs  for  a 
number  of  systems  in  that  State.  The  average  of  16  systems 
scattered  over  the  State  gives  the  following  division  of  the  total 
expenses:  general  salaries,  17  per  cent.;  other  general  expenses, 
10  per  cent. ;  taxes,  6  per  cent. ;  operation  expense,  37  per  cent. ; 
maintenance  and  repairs,  30  per  cent.  These  do  not  include  the 
fixed  charges  such  as  interest  and  depreciation  which  have  been 
found  to  average  about  60  per  cent,  of  the  total  cost.  The  direct 
operation  expense  of  37  per  cent,  of  the  total  expenses  other 
than  fixed  charges  would  on  this  basis  be  only  15  per  cent,  of  the 
entire  rate  which  such  companies  would  be  entitled  to  earn.  In 
addition  to  the  cases  actually  coming  before  the  commission  for 
rate-fixing,  all  irrigation  utility  companies  report  their  ex- 
penditures annually  under  a  standard  form  of  accounts.  In 
1914  the  reports  of  26  companies  show  an  average  of  34  per 
cent,  of  the  expenses  other  than  fixed  charges  to  have  been  for 
operation,  a  practical  agreement  with  the  figures  in  the  actual 
rate  cases. 

In  Bulletin  229  of  the  Office  Experiment  Stations,  U.  S.  De- 
partment of  Agriculture,  "Delivery  of  Water  to  Irrigators,"  by 
Frank  Adams,  the  cost  of  delivery  alone  for  a  number  of  systems 
is  given.  For  six  systems  outside  of  southern  California  the 
cost  of  delivery  to  individual  farms  averaged  16  cents  per  acre 
per  season;  for  seven  systems  delivering  to  the  heads  of  laterals 
only  the  cost  averaged  10  cents  per  acre  per  season.  For  nine 
systems  in  southern  California  delivering  to  10-  to  20-acre  hold- 
ings where  small  measured  heads  are  used  during  a  long  irriga- 
tion season  the  average  cost  per  acre  for  delivery  was  71  cents. 
These  costs  include  only  delivery  of  water  and  the  superin- 
tendence directly  chargeable  to  such  delivery.  If  the  census 
figure  of  $1.07  per  acre  for  total  operation  and  maintenance  cost 
is  used  and  13  cents  taken  as  the  cost  of  delivery  alone,  the 
percentage  of  cost  of  service  to  be  returned  by  the  quantity  rate 
is  quite  small. 


CONSTRUCTION  AND  OPERATION  CHARGES       201 


The  reports  of  the  U.  S.  Reclamation  Service  give  costs  of 
operation  and  maintenance  separately.  For  all  projects  the 
costs  to  June  30,  1916,  are  given  in  Table  XX. 

TABLE  XX. — TOTAL  COST  OF  OPERATION  AND  MAINTENANCE  ON  ALL  PRO- 
JECTS OF  U.  S.  RECLAMATION  SERVICE  TO  JUNE  30,  1916 


Operation 

Maintenance 

Total 

Per 
cent, 
of 
total 

Opera- 
tion per 
cent,  of 
total 

Storage  

$176,000 

$234,000 

$410,000 

8 

43 

Pumping  for  irrigation.  . 
Canal  systems  

344,000 
439,000 

45,000 
859,000 

389,000 
1,298,000 

8 

25 

89 
34 

Lateral  system  
Undistributed  expenses  . 

850,000 
147,000 

1,681,000 
316,000 

2,531,000 
463,000 

50 
9 

34 
32 

Total.             

$1,956,000 

$3,135,000 

$5,091,000 

100 

38 

The  use  of  the  quantity  rate  has  long  been  advocated  by  those 
responsible  for  the  general  policies  of  the  U.  S.  Reclamation 
Service.  This  method  was  used  to  some  extent  on  projects 
operated  on  a  rental  basis  prior  to  1915,  and  was  made  general 
at  that  time  under  the  terms  of  the  Extension  Act,  passed  in 
1914.  As  these  various  projects  are  distributed  throughout  all 
the  Western  States,  the  rates  used  in  1916  represent  the  wide 
variations  required  to  meet  different  conditions.  The  following 
information  has  been  taken  from  the  public  notices  for  the  1916 
rates  issued  for  the  different  projects. 

The  initial  charge  was  made  relatively  high,  in  order  to  dis- 
courage speculative  holdings,  usually  1  to  2  acre-feet  per  acre 
being  furnished  for  the  initial  charge,  which  applies  to  all  irri- 
gable land,  whether  water  is  used  or  not.  The  rates  per  acre-foot 
for  water  in  excess  of  that  furnished  for  the  initial  charge  varied 
from  $0.10  to  $0.75  on  the  different  projects.  On  these  projects 
having  the  greatest  variety  of  soil  types,  the  lowest  rates  on 
excess  water  were  used.  On  the  Truckee-Carson  project  the 
rates  were  90  cents  for  the  first  acre-foot  per  acre  and  10  cents 
per  acre-foot  for  the  additional  amounts  used.  Rates  of  this 
type  are  required  in  order  not  to  unduly  penalize  the  owner  of 
porous  lands  for  a  condition  which  is  beyond  his  means  to  remedy. 
On  the  basis  of  the  average  use  of  water  in  1915  and  the  rates  for 
1916  the  initial  charge  was  equal  to  about  80  per  cent,  of  the  total 
charge  on  lands  using  the  average  amounts  of  water.  Includ- 


202  IRRIGATION  SYSTEMS 

ing  the  collections  from  land  not  irrigated,  probably  more  than 
this  proportion  of  the  total  operation  charges  were  derived  from 
the  initial  charge.  The  charges  for  excess  water,  while  furnishing 
only  a  minor  part  of  the  total  charges,  act  as  a  restriction  on 
excess  use.  Various  special  rates  were  required  on  the  different 
projects,  such  as  different  rates  for  direct  flow  and  storage  water, 
and  for  extreme  types  of  soil. 

The  annual  statements  of  different  irrigation  companies  are 
not  all  made  on  the  same  basis  or  in  the  same  detail  so  that  it  is 
difficult  to  pick  out  the  items  which  represent  the  demand  cost 
and  those  which  represent  the  service  cost.  An  examination 
of  a  number  of  such  reports  was  made,  the  general  ratio  between 
operation,  maintenance  and  general  expense  being  similar  to 
the  other  figures  given. 

The  examples  indicate  that  the  delivery  costs  do  not  average 
over  one-third  of  the  total  operation  and  maintenance  cost 
exclusive  of  fixed  charges.  If  rates  are  based  on  cost  of  service 
and  do  not  include  interest  on  the  value  of  the  system,  the 
minimum  charge  should  be  adjusted  to  return  from  two-thirds 
to  three-fourths  the  total  cost,  and  the  remainder  be  secured  from 
the  delivery  charges.  If  interest  on  the  value  is  included  in  the 
rate,  the  minimum  or  demand  charge  should  cover  four-fifths  to 
five-sixths  the  total  payment.  As  the  minimum  charge  is  prac- 
tically an  acreage  charge,  such  rates  are  more  nearly  on  a  flat 
acreage  basis  than  on  a  quantity  basis. 

Variations  in  Rates  from  Cost  of  Service.— In  many  cases  it 
may  not  be  desirable  to  base  the  rates  on  the  cost  of  service. 
For  the  same  reasons  that  power  companies  or  railroads  may  find 
it  preferable  to  base  rates  on  the  value  of  the  service,  canal  com- 
panies may  find  it  preferable  to  increase  the  quantity  rates  so  as 
to  furnish  a  larger  proportion  of  the  return.  A  quantity  rate 
based  on  the  cost  of  delivery  may  be  so  low  as  to  offer  little  incen- 
tive to  careful  use.  This  results  in  charging  higher  rates  per 
acre-foot  for  excess  water  or  in  a  reduction  in  the  quantity  fur- 
nished for  the  minimum  charge.  When  the  conditions  are  uni- 
form so  that  the  value  of  an  acre-foot  of  water  to  the  land  on 
which  it  is  used  is  similar  for  all  parts  of  the  system,  higher 
quantity  rates  are  desirable.  This  is  also  true  where  the  supply 
is  less  than  the  amounts  which  it  may  be  desirable  to  use ;  in  such 
cases  a  high  quantity  rate  will  tend  to  restrict  use  to  the  crops  of 
higher  return.  Where,  however,  the  supply  is  ample  and  a  canal 


CONSTRUCTION  AND  OPERATION  CHARGES       203 

system  has  little  opportunity  of  disposing  of  water  which  may  be 
saved  by  a  high  quantity  rate,  there  would  seem  to  be  little 
advantage  in  quantity  rates  higher  than  the  cost  of  service.  A 
high  quantity  rate  may  indirectly  reduce  the  need  of  drainage 
if  it  acts  to  restrict  use.  Where  late  season  water  is  secured  from 
storage  a  higher  quantity  rate  for  such  water,  proportional  to 
its  actual  cost,  which  is  on  a  quantity  basis,  may  be  used. 

The  principal  advantage  of  the  quantity  method  of  charges  is 
the  incentive  to  more  careful  use.  The  annual  cost  of  water  to 
any  farm  depends  upon  the  amount  used,  and  careful  use  pro- 
duces a  direct  return  in  the  reduction  of  the  charges.  If  the 
annual  operation  cost  is  determined  wholly  by  the  area  irri- 
gated, as  in  the  flat  rate  per  acre  method,  there  is  no  direct  saving 
to  the  individual  on  such  charges  due  to  a  careful  use  of  water. 
In  many  localities  the  cost  of  water  is  less  than  the  cost  of  its 
application  to  the  land.  In  such  cases,  the  cost  of  application 
acts  to  some  extent  to  prevent  unnecessary  use.  This  is  true  to 
a  greater  extent  in  regard  to  the  number  of  irrigations  than  to 
the  amount  applied  at  each  irrigation. 

It  is  usual  also  to  furnish  a  certain  quantity  of  water  per  acre 
for  this  minimum  or  initial  charge,  more  often  1  acre-foot.  This 
minimum  charge  may  be  assessed  against  all  irrigable  land,  or 
only  against  land  actually  irrigated  in  any  year.  It  is  preferable 
to  assess  all  irrigable  land.  This  discourages  speculative  holdings 
and  requires  any  land  supplied  by  subirrigation  or  waste  to  bear 
a  portion  of  the  cost.  The  cost  of  this  "readiness  to  serve"  is 
more  largely  a  factor  of  the  irrigable  area  under  the  system  than 
of  the  area  which  may  be  irrigated  in  any  year.  Charging  all 
irrigable  land  with  this  minimum  cost  may  work  a  hardship  on 
some  settlers  during  the  first  year  of  settlement  when  they  are 
unable  to  prepare  all  of  their  land  for  irrigation.  However,  if 
the  total  cost  of  service  must  be  met  by  the  total  charges,  the 
assessing  of  an  initial  charge  against  all  irrigable  land  will  reduce 
the  rate  for  excess  water,  so  that  the  total  cost  to  the  average  farm 
may  not  be  materially  changed.  The  quantity  of  water  fur- 
nished for  the  minimum  charge  should  be  somewhat  less  than  the 
quantity  used  under  better  practice  on  the  system.  This  penal- 
izes any  excess  use  over  the  amounts  actually  needed.  On 
many  systems  which  have  been  handled  on  the  flat  rate  per  acre 
basis,  changes  to  the  quantity  rate  are  being  agitated.  Such 
changes  from  a  method  which  is  understood  to  one  involving 


204  IRRIGATION  SYSTEMS 

measurements  with  which  the  usual  farmer  is  unfamiliar  are 
naturally  opposed  more  or  less  actively  by  the  users.  This  is 
largely  a  prejudice  against  any  change,  the  results  of  which  are 
not  understood.  For  this  reason  it  may  be  desirable  to  make 
the  rates  on  excess  quantities  of  water  quite  low,  at  least  for  the 
first  few  years  after  the  adoption  of  the  quantity  rates,  so  that 
the  added  charge  for  less  economical  use  will  be  relatively  small. 
An  initial  charge,  which  practically  will  return  the  cost  of  opera- 
tion with  a  rate  on  excess  water,  which  will  somewhat  more  than 
return  the  added  cost  of  measurement,  may  be  used.  This  may 
have  a  good  effect  in  causing  the  users  to  give  attention  to  the 
quantities  of  water  used  and  in  securing  data  on  the  actual  use 
without  at  first  giving  sufficient  added  cost  to  those  using  excess 
amounts  to  cause  active  opposition.  The  charges  may  later  be 
developed  to  penalize  wasteful  use  to  a  greater  extent  and  so 
have  a  greater  effect  in  reducing  its  amount. 

In  some  cases  special  rates  may  be  given  for  the  first  1  to  3 
years'  irrigation  on  new  lands.  It  is  recognized  that  raw  lands 
usually  require  more  water  than  the  same  land  after  it  has  been 
in  use  for  a  longer  time.  The  interest  of  the  canal  system  is  more 
largely  in  stimulating  development,  rather  than  in  forcing  the 
most  economical  use  at  first. 

Variations  in  Rates  Due  to  Soil  Conditions. — Where  the  condi- 
tions on  different  parts  of  a  system  vary  and  where  the  value  of 
the  crops  limits  the  price  which  can  be  paid  for  water,  various 
special  forms  of  rates  will  be  required  if  the  quantity  basis  is  to 
give  equitable  results.  This  is  particularly  true  on  systems  where 
all  lands  have  been  handled  on  a  flat  acreage  basis  for  construc- 
tion and  operation  charges  and  a  change  to  a  quantity  rate  is 
made.  The  more  usual  variations  in  use  which  occur  are  those 
due  to  differences  in  soils,  a  factor  largely  beyond  the  control  of 
the  irrigator.  Where  the  areas  of  the  different  types  of  soil  are 
relatively  distinct,  district  or  zone  rates  may  be  used  for  the 
different  conditions.  Usually,  however,  such  soil  variations 
blend  into  one  another  so  that  the  divisions  of  the  zones  will  not 
be  distinct.  If  the  larger  proportion  of  the  land  is  uniform  and 
the  number  of  farms  requiring  special  rates  relatively  small,  the 
method  of  rebates  used  on  the  Boise  project  will  give  good  results. 
On  this  project  when  the  total  charges  for  any  farm  under  the 
usual  rates  exceeds  $2  per  acre  irrigated,  provision  is  made  for  an 
examination  of  the  land  by  a  committee  of  water  users.  If  the 


CONSTRUCTION  AND  OPERATION  CHARGES       205 

ditches  are  found  to  be  in  good  conditions,  the  land  well-prepared 
and  the  water  carefully  used,  a  rebate  of  the  charges  in  excess  of 
$2  per  acre  may  be  made. 

The  experience  of  the  gravity  unit  of  the  Minidoka  project  is  of 
interest  in  this  connection.  This  system  was  operated  on  a  flat 
acreage  rate  until  the  passage  of  the  Extension  Act  requiring  the 
use  of  the  quantity  rate.  In  1914  the  rates  were  75  cents  per  acre. 
In  1915  the  minimum  charge  was  60  cents  per  acre  for  which  1 
acre-foot  was  supplied  plus  5  cents  per  acre-foot  for  any  excess 
water  used.  The  actual  average  use  varies  from  2  to  8  acre-feet 
on  different  soils  on  this  system,  so  that  even  the  very  low  rate  for 
excess  water  made  a  material  difference  in  the  charges.  In  1916 
a  zone  system  was  established.  Three  zones  were  used,  the  mini- 
mum charge  in  each  being  75  cents  per  acre,  for  which  1,  3  and  6 
acre-feet  per  acre  respectively  were  supplied  in  each  zone.  For 
excess  water  a  uniform  rate  of  15  cents  per  acre-foot  was  used. 
While  some  hardship  may  result  from  this  rate  along  the  division 
of  the  zones  which  were  necessarily  fixed  to  fit  average  conditions, 
for  the  system  as  a  whole  the  1916  rate  should  be  much  more 
equitable  than  that  used  in  1915. 

On  the  Okanogan  project  a  flat  rental  charge  of  $3  per  acre 
was  used  in  1914.  In  1915,  three  zones  based  on  the  quality 
of  the  soil  were  used.  A  minimum  charge  to  all  lands  of  $1.75 
per  acre  was  used  for  which  the  better  lands  were  given  1  acre-foot 
per  acre,  the  medium  lands  1 J^  acre-feet  and  the  poorer  or  sandier 
lands  2  acre-feet,  all  lands  paying  $1.50  per  acre-foot  for  any 
water  used  in  excess  of  these  minimum  amounts.  This  system 
of  charges  provided  a  sufficient  revenue  and  at  the  same  time 
caused  an  actual  decrease  in  the  amount  of  water  used. 

The  need  for  recognizing  variations  in  soil  in  fixing  rates  on 
the  quantity  basis  has  been  felt  by  the  U.  S.  Reclamation  Ser- 
vice since  the  passage  of  the  Extension  Act.  The  following 
quotation  from  the  15th  Annual  Report  after  2  years  operation 
of  all  projects  on  a  quantity  rate  is  instructive: 

"Additional  experience  gained  during  this  period  further  indicates 
the  desirability  for  reasonably  close  classification  of  the  soils  on  some 
of  the  projects  with  respect  to  the  duty  of  water  on  the  various  types. 
An  acre-foot  of  water  delivered  to  porous  or  sandy  soil  will  not  per- 
form the  same  duty  as  the  same  amount  delivered  to  non-porous  soil 
and  the  value  of  the  water  is  correspondingly  less  to  the  irrigationist. 
Such  a  classification  of  soils  has  been  fairly  well  worked  out  on  the 


206  IRRIGATION  SYSTEMS 

Minidoka  project  in  Idaho,  where  the  Department  of  Agriculture  made 
soil  classification  and  duty  of  water  studies  during  the  season  of  1915. 
Pending  a  proper  classification  of  soils,  the  fixing  of  operation  and 
maintenance  charge  schedules  in  such  manner  as  to  approximate  a 
flat  rate  per  acre  will  prevent  serious  inequities  among  water  users  on 
projects  where  the  types  of  soil  vary  considerably." 

A  quantity  rate  is  not  suited  to  localities  where  irrigation  is 
only  supplemental  to  the  precipitation  and  where  the  use  of 
irrigation  water  varies  widely  from  year  to  year.  The  returns 
to  the  irrigation  company  in  such  cases  are  uncertain.  Unless 
the  land  can  be  held  by  some  form  of  contract  to  pay  the  demand 
charges  whether  water  is  used  or  not,  either  as  a  flat  acreage 
charge  or  as  the  minimum  charge  in  a  quantity  rate,  there  is 
little  assurance  of  an  adequate  earning  for  the  system.  Flat 
acreage  rates  are  preferable  for  such  conditions. 

TERMS  OF  PAYMENT 

Operation  charges  may  be  paid  monthly  or  at  one  payment  for 
the  whole  season,  the  latter  method  being  more  usual.  Monthly 
payments  are  used  on  some  systems  delivering  on  a  quantity 
rate.  In  case  water  received  during  the  previous  month  is  not 
paid  for  by  some  fixed  date  in  the  month  following,  further  de- 
livery may  be  refused.  On  many  systems  payment  is  made  at 
the  end  of  the  season  after  the  crops  produced  with  the  water 
have  been  harvested.  With  cooperative  systems,  the  assess- 
ments are  made  at  various  times  during  the  year  as  need  arises, 
and  amount  to  a  payment  in  advance  in  most  cases.  In  irri- 
gation districts  the  expenses  for  the  following  year  are  estimated, 
so  as  to  be  collected  with  the  other  taxes  during  the  preceding 
winter,  which  is  also  a  payment  in  advance.  With  the  Reclama- 
tion Service  payments  are  now  due  on  March  1  of  the  year  fol- 
lowing. This  enables  the  crops  to  be  both  harvested  and  sold 
before  payment  for  the  water  used  in  their  production  is  made. 
Most  private  systems  owned  by  others  than  the  users  cannot 
carry  the  accounts  to  this  extent.  This  can  be  done  by  the 
Reclamation  Service,  as  their  funds  are  not  subject  to  interest 
rates.  Advance  payments  can  be  more  easily  made  where  the 
flat  rate  per  acre  basis  is  used,  as  the  amount  of  the  charge  can 
be  determined  in  advance. 

Interest  on  delinquent  payments  is  usually  charged  at  rates 


CONSTRUCTION  AND  OPERATION  CHARGES       207 

varying  from  6  to  12  per  cent.  For  irrigation  district  assess- 
ments, the  penalties  on  overdue  taxes  are  equivalent  to  such 
interest  charges.  The  Reclamation  Service  now  charges  the 
users  1  per  cent,  per  month  on  delinquent  accounts,  but  also 
gives  a  rebate  of  5  per  cent,  for  payments  made  before  due. 

SUMMARY 

In  general  it  may  be  concluded  that  some  form  of  quantity 
rate  is  preferable  although  the  preference  for  this  type  of  rate 
comes  more  largely  from  other  causes  than  its  relation  to  the  cost 
of  service.  Even  where  the  quantity  rate  is  only  sufficient  to 
cover  the  added  cost  of  measurement  of  individual  deliveries, 
its  use  may  be  of  benefit  in  causing  a  realization  among  the  users  of 
the  importance  of  care  in  the  use  of  water  and  in  furnishing  a  basis 
for  later  changes  in  rates  so  as  to  more  largely  penalize  wasteful 
use. 

The  result  of  the  change  to  quantity  rates  on  the  U.  S.  Reclama- 
tion Service  projects  is  well  expressed  in  the  15th  Annual  Report: 

"  While  the  basing  of  operation  and  maintenance  charges  on  the 
amount  of  irrigation  water  used  per  acre  has  worked  some  disadvantages 
due  to  varying  types  of  soil,  this  plan  has  worked  economies  in  the 
handling  of  project  works  as  the  water  has  been  used  more  conserva- 
tively and  more  timely  irrigations  have  been  effected.  The  irrigation- 
ists  are  now  studying  the  use  of  water,  which  is  beneficial  to  both  the 
land  and  the  land  owner." 

Two  tendencies  toward  improvement  in  methods  are  notice- 
able in  irrigation  operation,  the  tendency  toward  rotation 
methods  of  delivery  and  the  tendency  toward  the  use  of  rates 
based  at  least  in  part  on  the  quantity  of  water  used.  While 
neither  rotation  delivery  or  quantity  rates  are  suited  to  all  condi- 
tions encountered  in  irrigation,  they  are  adapted  in  many  situa- 
tions where  other  methods  are  now  used  and  the  extension  of  their 
use  is  to  be  expected  and  should  be  encouraged.  Quantity  rates, 
however,  should  not  be  adopted  without  a  full  understanding  of 
the  local  conditions  and  of  the  effect  which  the  rate  selected  will 
have  upon  the  use  of  water  and  the  charges  to  individuals  for  the 
conditions  found  on  the  system.  A  well-chosen  division  of  costs 
between  the  minimum  charge  and  the  service  rate  should  be  better 
than  flat  rates  on  the  large  majority  of  systems;  a  poorly  chosen 
division  may  result  in  a  permanent  reversion  to  flat  rates. 


208  IRRIGATION  SYSTEMS 

REFERENCES  FOR  CHAPTER  VII 

ADAMS,  F. — Delivery  of  Water  to  Irrigators,  1910,  Bulletin  229,  Office  of 
Experiment  Stations,  U.  S.  Department  of  Agriculture. 

Irrigation,  Chapter  XI,  Vol.  V,  Agriculture,  Thirteenth  Census  of  the 
United  States. 

Operation  of  the  Reclamation  Extension  Act,  Reclamation  Record,  Novem- 
ber, 1914. 

FISHER,  C.  C. — Rules  to  be  Adopted  in  the  Determining  of  the  Irrigable 
Acreage  of  the  Individual  Farm,  1915,  Fourth  Conference  of  Operating 
Engineers,  Boise,  Idaho. 

Present  Worth  of  Payments  on  U.  S.  Reclamation  Service  Charges, Reclama- 
tion Record,  February,  1916. 

PETERS,  F.  H. — A  Complete  Method  for  the  Classification  of  Irrigable 
Lands,  1916,  Proceedings  American  Society  of  Civil  Engineers,  Vol. 
XLII. 

Operation  Expenses  of  California  Irrigation  Companies,  Journal  of  Elec- 
tricity, Power  and  Gas,  Sept.  9,  1916. 

Public  Notices  for  Projects  of  U.  S.  Reclamation  Service,  Washington,  D.  C. 

Fifteenth  Annual  Report  of  U.  S.  Reclamation  Service,  1916,  Washington, 
D.  C. 

WALLER,  O.  L. — Assessment  of  Irrigation  Charges,  1916,  Third  Proceedings 
Washington  Irrigation  Institute,  No.  Yakima,  Wash. 


CHAPTER  VIII 

GENERAL  OPERATION 
USE  OF  CHECKS  IN  CANALS 

Where  the  water  surface  of  a  canal  is  not  sufficiently  above  the 
adjacent  ground  surface  to  permit  direct  delivery,  checks  must 
be  used  in  the  canals.  This  condition  occurs  for  many  canals 
when  operated  at  capacity;  it  also  occurs  with  nearly  all  canals 
from  which  deliveries  at  part  capacity  have  to  be  made,  a  condi- 
tion that  occurs  at  the  beginning  and  end  of  the  irrigation  season. 
If  the  land  does  not  have  a  regular  slope  away  from  the  canal 
it  is  difficult  to  cover  all  the  land  below  the  ditch,  unless  the  ditch 
is  carried  in  fill.  It  may  be  cheaper  not  to  attempt  to  serve  small 
areas  of  high  land  than  to  try  to  hold  the  ditches  sufficiently  high 
to  cover  them. 

Main  canals  cannot  be  divided  and  the  flow  taken  into  main 
laterals  without  checks  unless  excessively  large  gates  or  consider- 
able fall  into  the  lateral  is  available.  Checking  the  canal  from 
which  the  lateral  diverts  gives  greater  pressure  on  the  gates  so 
that  smaller  sizes  can  be  used.  Checking  main  canals  gives  un- 
favorable conditions  for  canal  rating;  the  methods  of  handling 
such  stations  are  discussed  under  canal  hy drography  in  Chapter  V. 

The  use  of  checks  decreases  the  velocity  in  the  canal  and  may 
cause  silting.  This  can  be  lessened  near  the  checks  by  having 
openings  near  the  bottom ;  the  effects  of  such  sluicing  may  extend 
only  short  distances,  however.  By  operating  the  canal  as  a  whole 
without  checks  at  the  beginning  or  end  of  the  season  when  delivery 
is  not  required,  it  may  be  possible  to  sluice  out  such  deposits. 

It  is  not  usually  necessary  that  checks  be  water-tight,  as  they 
are  more  often  used  to  control  the  delivery  of  a  portion  of  the 
water  by  raising  the  water  surface  than  to  stop  the  flow  entirely. 
This  is  particularly  true  of  the  larger  canals.  Gates  having 
heights  somewhat  less  than  the  depth  of  the  canals  or  flashboards 
can  be  used.  Flashboards  can  be  made  small  enough  to  be 
handled  by  one  man.  Sliding  gates  are  usually  operated  by  hand 
through  some  form  of  levers  or  gears.  Taintor  gates  can  be 

209 


210  IRRIGATION  SYSTEMS 

operated  by  one  man.  Check  gates  may  be  made  to  operate 
automatically  so  as  to  hold  the  water  surface  at  a  constant  level. 
The  automatic  regulation  is  applied  usually  to  only  one  bay  or 
division  of  the  checks,  the  others  being  hand-operated. 

Checks  may  pass  the  water  either  at  the  bottom  or  at  the  top 
of  the  canal  section.  If  the  drop  at  the  check  is  more  than  1  foot, 
the  velocity  through  undershot  checks  may  be  sufficient  to  cause 
erosion  in  the  canal  below,  unless  lining  or  other  preventative 
methods  are  used.  With  over  pour  checks  this  fall  can  be  more 
easily  controlled  in  the  stilling  basin  at  the  fall.  A  combination 
in  which  some  openings  act  as  undershot  and  some  as  overpour 
checks  may  be  preferable  to  all  of  either.  Overpour  checks  are 
less  affected  by  fluctuations  in  the  discharge  of  the  canal  as  the 
discharge  is  proportional  to  the  three-half  power  of  the  head 
instead  of  the  one-half  power  of  the  difference  in  head  as  with 
submerged  orifices. 

Delivery  gates  should  be  placed  as  near  the  bottom  of  canals 
as  practicable  in  order  that  delivery  can  be  made  at  low  stages 
of  the  canal.  Where  such  deliveries  are  only  a  small  proportion 
of  the  water  being  carried  in  the  canal,  diversion  can  be  made 
through  such  gates  without  checking  the  main  canals  if  the  deliv- 
ery gate  does  not  serve  land  too  high  in  relation  to  the  canal.  The 
elevation  of  the  canal  should  be  adjusted  to  that  of  the  land  to  be 
served  so  that  checking  for  small  deliveries  is  not  required  on 
main  canals  or  larger  laterals.  On  smaller  laterals  where  each 
delivery  receives  a  large  proportion  of  the  total  flow,  checking  for 
delivery  is  usually  required. 

When  the  canals  carry  water  only  part  of  the  time  or  where  a 
check  is  used  only  for  a  few  days  per  month  to  make  certain 
deliveries,  less  freeboard  may  be  needed  than  where  the  banks 
are  under  continuous  strain.  On  the  other  hand,  the  danger 
from  breaks  on  such  banks,  due  to  gopher  or  squirrel  holes, 
is  greater  than  on  those  where  the  water  is  held  at  a  constant 
elevation. 

WASTE  WATER  FROM  FARMS 

There  are  two  kinds  of  waste  which  may  occur  after  water  has 
been  delivered  to  farms.  One  of  these  is  the  surface  runoff  or 
visible  waste.  The  other  is  the  deep  percolation  loss  or  invisible 
waste.  The  farmer  is  responsible  for  the  disposal  of  the  first  of 


GENERAL  OPERATION  211 

these  as  it  can  be  traced  to  its  source  and  the  responsibility 
fixed.  The  second  class,  from  its  nature,  can  hardly  be  traced 
to  its  individual  source  and  while  accumulated  seepage  often 
causes  more  damage  to  lower  lands  than  surface  waste  the  respon- 
sibility cannot  be  directly  fixed. 

Surface  waste  will  occur  to  some  extent  under  all  conditions 
of  irrigation.  It  cannot  be  entirely  eliminated  any  more  than 
waste  in  canal  operation  can  be  entirely  avoided.  Surface  waste 
from  the  irrigated  lands  may  amount  to  20  or  30  per  cent,  of  the 
water  applied  to  some  fields;  it  should  not  exceed  10  per  cent,  for 
any  farm  or  5  per  cent,  for  any  canal  system.  The  amount  of 
surface  waste  depends  on  several  factors  among  which  are:  (1) 
ability  to  dispose  of  the  water,  (2)  method  of  irrigation  and  pre- 
paration of  the  land,  (3)  value  of  water,  (4)  kind  of  soil,  (5)  skill 
of  irrigator  and  (6)  size  of  irrigation  head. 

Where  the  use  of  water  is  obviously  wasteful  it  can  be  shut  off. 
Most  canal  systems  include  such  a  rule  in  their  regulations.  This 
is  used,  however,  only  where  the  waste  is  of  such  extent  as  to 
attract  attention  and  cannot  be  expected  to  prevent  ordinary 
waste.  The  laws  of  most  States  also  provide  means  for  the 
closing  of  canal  headgates  served  under  appropriation  rights  if 
water  is  not  being  used  beneficially.  Most  States  have  laws 
making  it  a  misdemeanor  to  permit  the  running  of  waste  water 
onto  county  roads.  An  occasional  prosecution  under  such  laws 
will  have  a  beneficial  effect.  Where  roads  are  well  crowned  and 
have  good  side  ditches,  waste  water  may  be  carried  along  the 
right  of  way  of  the  road  until  it  reaches  an  outlet  without  damage 
to  the  road. 

Rights  to  waste  water  are  still  the  source  of  much  legal  con- 
troversy. In  general,  waste  water  is  subject  to  appropriation 
if  taken  before  it  reaches  a  natural  drainage  channel  or  stream, 
after  which  it  becomes  subject  to  the  rights  in  the  stream.  Such 
waste-water  rights,  however,  do  not  compel  the  one  whose  waste 
water  is  thus  appropriated  to  continue  the  waste.  Where  laterals 
are  run  around  the  slope  of  the  land  instead  of  down  the  steepest 
grade,  provision  may  be  made  for  picking  up  waste  from  higher 
lands.  This  is  of  questionable  benefit,  however,  as  the  amounts 
received  are  usually  too  variable  to  be  dependable  and  may  at 
times  be  sufficient  to  overload  the  lateral.  It  is  more  usual  for 
the  land  owner  to  provide  his  own  outlet  to  the  nearest  drainage 
channel.  Where  closed  drainage  systems  have  been  built,  it  is 


212  IRRIGATION  SYSTEMS 

not  usual  to  permit  surface  waste  to  be  discharged  into  them  as 
the  capacities  of  the  closed  drains  are  inadequate  for  such  use. 

WASTEWAYS 

Waste  ways  serve  two  principal  purposes:  (1)  relief  in  case  of  a 
canal  break  below  the  wasteway:  (2)  regulation  of  the  supply 
carried.  For  the  second  purpose,  the  wasteways  or  spillways 
are  located  just  below  the  point  of  diversion,  at  the  ends  of  canals 
and  laterals  to  give  an  outlet  for  unused  water  and  at  points 
within  the  system  where  outlets  can  be  secured.  For  the  first 
purpose  wasteways  should  be  located  above  dangerous  lengths  of 
canal  to  enable  the  flow  to  be  turned  out  quickly  in  case  of 
breaks.  In  sidehill  locations  liable  to  breaks,  wasteways  may  be 
desirable  at  distances  of  from  3  to  5  miles.  The  actual  damage 
caused  by  a  break  is  usually  proportional  to  the  time  which 
elapses  before  water  can  be  shut  off,  which,  in  turn,  depends  on 
the  distance  of  the  break  from  the  nearest  wasteway  above. 
Such  wasteways  are  more  essential  on  main  canals  than  on 
laterals.  When  breaks  in  laterals  occur,  the  water  can  often  be 
crowded  into  other  laterals. 

Speed  and  ease  in  operation  are  essential  in  wasteways  used 
for  relief  in  case  of  breaks.  Taintor  gates  have  this  advantage. 
Ordinary  geared  slide  gates  are  slow  in  operation  unless  power- 
driven.  Such  wasteways  should  be  set  low  enough  to  draw  the 
full  flow  from  the  canal  or  a  check  should  be  built  across  the  canal 
below  the  wasteway.  Control  of  the  high-water  line  may  be 
secured  by  using  lip  spillways  set  at  the  full-supply  water  sur- 
face. If  the  water  is  raised,  due  to  clogging  of  screens  or  similar 
causes,  partial  relief  may  be  secured  by  such  spillways.  For 
close  control  an  excessive  length  of  crest  is  required,  for  this  type 
of  spillway.  This  disadvantage  may  be  overcome  by  the  use  of 
siphon  spillways,  where  the  conditions  are  suited  to  their  use. 

In  some  cases  provision  is  made  for  carrying  cross-drainage  into 
or  through  the  canal.  Waste  gates  may  be  placed  in  both  the 
upper  and  lower  banks.  In  flat  country  it  may  be  difficult  to 
locate  the  canal  so  that  such  drainage  can  be  taken  either  under 
or  over  the  canal,  although  such  methods  are  usually  preferable. 
Drainage  during  the  non-operating  season  may  be  carried  directly 
through  the  canal.  During  the  operation  season  it  may  be  used 
or  wasted  depending  on  the  relative  amounts  of  such  drainage 
and  the  capacity  of  the  canal. 


GENERAL  OPERATION  213 

Some  wasteways  are  designed  to  be  automatic  in  their  action, 
opening  when  the  canal  either  rises  or  falls  below  certain  limits. 
Such  devices,  if  not  tested  frequently,  are  liable  to  fail  to  work 
when  desired.  For  canals  in  unstable  locations  it  will  be  desir- 
able to  have  low  and  high-water  alarms  connected  with  the 
patrolmen's  quarters  so  that  they  can  be  called  out  at  any  time. 

STOCK  WATER 

Irrigation  systems  may  be  used  to  furnish  water  for  stock  and 
even  for  domestic  use  as  well  as  for  irrigation.  In  some  locali- 
ties, particularly  for  the  larger  systems  covering  bench  lands, 
the  expense  of  drilling  the  deep  wells  required  and  the  uncertainty 
as  to  the  supply  which  will  be  secured,  make  it  necessary  to  use 
canal  water  for  such  purposes.  Little  can  be  said  in  favor  of  the 
direct  use  of  canal  water  for  domestic  purposes  except  in  those 
limited  areas  where  the  supply  is  pumped  from  the  ground  water 
and  conveyed  without  pollution.  Even  if  well  supplies  cannot 
be  secured,  the  canal  water  can  be  filtered  into  a  cistern  for  house 
use.  Such  filter  and  cistern  should  be  regarded  as  one  of  the 
improvements  the  settler  is  expected  to  make  if  no  other  domestic 
supply  is  available. 

Stock  water  may  be  supplied  both  during  the  main  irrigation 
season  and  also  after  crop  use  is  ended.  Where  continuous- 
flow  delivery  methods  are  used  stock  water  requires  little  addi- 
tional delivery  during  the  irrigation  season.  For  demand  or 
rotation  delivery  to  the  crops,  a  small  continuous  stream  may 
be  needed  for  stock  use.  The  amount  of  such  stock  water  is 
generally  too  small  to  warrant  its  separate  measurement.  If 
the  charges  for  water  are  based  on  the  quantity  used,  a  certain 
arbitrary  charge  may  be  added  for  such  service.  Where  the 
system  is  operated  for  stock  use  alone  outside  of  the  irrigation 
season,  the  costs  should  be  borne  by  those  benefited.  Winter 
operation  may  be  necessary  where  large  numbers  of  feeding  stock 
are  carried.  For  the  ordinary  work  stock  and  domestic  use  it 
may  be  possible  to  haul  water  or  to  use  cisterns.  The  colder 
canal  water  has  been  found  to  be  less  satisfactory  for  stock  than 
the  warmer  well  water. 

.  It  is  generally  found  that  after  irrigation  has  been  practised 
for  a  few  years,  well  supplies  become  available  due  to  the  rise 
of  the  ground  water,  or  that  the  financial  condition  of  the  settlers 


214  IRRIGATION  SYSTEMS 

enables  them  to  drill  deep  wells.  Stock-water  delivery,  particu- 
larly during  the  winter  season,  should  be  looked  upon  as  a 
temporary  expedient  to  be  stopped  as  soon  as  practical. 

NUMBERING  CANALS  AND  TURNOUTS 

Some  method  of  numbering  canals  and  turnouts  is  needed  as 
a  basis  for  reference  on  maps  and  in  records.  Such  numbers 
or  names  serve  as  abbreviations. 

Main  laterals  may  be  designated  by  names,  letters  or  numbers. 
On  smaller  systems  all  laterals  may  be  given  names.  Such  names 
may  be  chosen  from  the  locality  served,  as  the  Dry  Gulch  lateral, 
or  named  after  some  land  owner  under  the  lateral,  the  location 
of  whose  land  is  well  known.  On  large  systems  similar  names 
may  be  used  for  the  main  laterals.  Main  laterals  may  be  given 
the  names  of  letters  in  order  from  the  head  of  the  main  canal,  such 
as  the  A  canal.  Laterals  taking  out  from  the  A  canal  may  be 
given  numbers  in  the  order  of  their  location  from  the  head  of  the 
main  lateral  such  as  A-l  lateral.  This  method  may  be  carried 
through  the  sub-laterals,  alternating  letters  and  numbers  as 
A-l-B-3  for  the  third  sub-lateral  taking  out  from  the  second 
lateral  on  the  A-l  canal.  Where  all  canals  and  laterals  are  built 
at  the  same  time  such  methods  can  be  used  to  advantage.  If  it 
is  later  found  that  additional  sub-laterals  are  needed  the  sequence 
of  numbers  is  either  broken  or  additional  divisions  used  such  as 
the  A-l-B-3^/2  sub-lateral.  This  difficulty  may  be  overcome  by 
giving  each  lateral  a  number  corresponding  to  the  distance  of  its 
headgate  from  the  head  of  the  canal  from  which  it  is  taken, 
usually  expressed  in  miles  and  tenths  as  the  A-5.1  for  a  lateral 
taking  out  from  the  A  canal  5.1  miles  below  its  head.  This 
method  is  used  more  largely  on  main  canals  and  laterals  than  on 
sub-laterals.  For  any  method,  key  or  index  maps  showing  the 
actual  names  should  be  supplied  to  the  ditch  riders  and  the  name 
marked  on  the  head  gate. 

For  individual  headgates  or  turnouts  it  may  be  more  convenient 
to  use  numbers  than  names.  Such  numbers  may  be  preferable 
in  ditch  riders'  records  as  they  are  more  likely  to  be  legibly 
written  than  names.  Such  numbers  can  be  branded  or  painted 
on  the  headgate  so  that  the  ditch  rider  does  not  have  to  refer  to 
lists  of  numbers  in  making  his  delivery  entries.  The  office 
records  can  carry  both  names  and  numbers  as  these  are  used  only 
in  the  headings  and  not  repeated  for  each  entry.  In  some  cases 


GENERAL  OPERATION  215 

the  ditch  riders  fill  in  both  names  and  numbers  in  their  field 
record.  The  legal  description  of  the  land  may  be  used,  but  this 
is  inconvenient  and  confusing  unless  some  simplified  system  of 
description  is  used.  Such  a  method  is  used  on  the  Minidoka 
project  and  is  well  suited  to  lands  subdivided  according  to  the 
U.  S.  Land  Survey  into  40-acre  areas.  A  standard  plat  of  a 
section  is  used  in  which  each  one-sixteenth  section  or  40-acre 
tract  is  given  a  letter  depending  on  its  position  in  the  section. 
These  begin  with  A  in  the  northeast  corner  and  run  alternately 
west  and  east  across  the  section  in  the  same  way  that  the  sections 
are  numbered  in  a  township,  the  southeast  40-acre  tract  being 
called  P.  The  numbers  for  each  turnout  are  selected  by  taking 
the  last  digit  of  the  township  number,  the  last  digit  of  the  range 
number,  the  entire  section  number  and  the  farm  unit  letter. 
Thus  the  turnout  for  Farm  Unit  A,  Sec.  26,  Tp.  9  S.,  R.  23  E. 
would  be  9326A;  for  Farm  .Unit  D,  Sec.  9,  Tp.  10  S.,  R.  23  E. 
it  would  be  039D.  If  a  farm  unit  has  more  than  one  headgate 
they  may  be  numbered  1  and  2  if  desired  (Plate  VI,  Fig.  C).  The 
complete  numbers  are  either  stamped  or  painted  on  the  headgate. 
On  smaller  systems  covering  less  than  one  township  the  numbers 
referring  to  the  township  may  not  be  needed. 

LOCKING  TURNOUTS 

Practice  regarding  the  locking  of  individual  headgates  varies 
from  the  locking  of  all  gates  against  both  opening  and  closing 
to  that  of  permitting  the  individual  land  owners  to  practically 
operate  their  own  turnouts.  Any  practice  regarding  locking 
should  be  uniformly  enforced,  at  least  on  the  different  laterals  or 
ditch  riders'  beats.  This  is  necessary  to  avoid  charges  of  favor- 
itism. Locking  devices  may  be  provided  but  not  used  as  long 
as  no  trouble  arises.  Some  managers  prefer  to  control  the  taking 
of  water  by  other  means.  If  complaints  arise  on  a  lateral  over 
the  distribution  of  the  water,  all  turnouts  would  be  locked.  It 
may  occasionally  be  desirable  to  lock  turnouts  near  roads  or 
schools  in  order  to  prevent  mischievous  interference  by  others 
than  the  water  users. 

A  lock  may  remove  the  sense  of  responsibility  for  fair  dealing 
on  the  part  of  some  land  owners.  The  need  for  locks  may  de- 
pend more  largely  on  the  individuality  of  the  ditch  rider  than 
on  any  other  factor.  A  rider  who  demonstrates  his  fairness  and 
ability  to  get  water  to  the  users  when  promised  will  give  much 


216  IRRIGATION  SYSTEMS 

less  cause  for  attempting  to  obtain  water  irregularly.  There  are 
statutes  against  changing  gates  and  the  unlawful  taking  of  water 
which  can  be  used  where  the  responsibility  for  any  such  taking 
can  be  fixed  and  where  public  opinion  will  support  such  action. 
The  example  of  a  few  cases  of  active  prosecution  resulting  in 
fines  may  have  a  greater  effect  than  many  locks.  Locks  may  be 
provided  and  used  only  during  the  time  of  maximum  demand. 
At  the  beginning  and  end  of  the  season  the  supply  may  be  ample 
in  proportion  to  the  demand  and  close  regulation  not  necessary. 

Locks  may  be  arranged  so  that  while  the  gates  can  be  lowered 
they  cannot  be  raised  beyond  a  certain  point.  This  can  be  done 
by  placing  a  lock  or  clamp  on  the  gate  stem  which  will  not  pass 
through  the  guides.  Such  locks  permit  the  water  to  be  shut  off 
by  the  user  but  prevent  the  taking  of  an  excess.  They  are  not 
desirable  on  canals  run  to  the  maximum  level  as  such  turned 
back  water  may  overload  the  canal  below.  On  closely  controlled 
systems  it  is  not  usual  to  permit  one  user  to  turn  back  water 
without  notice  to  the  ditch  rider  or  arrangement  with  some  other 
owner  for  its  use. 

The  method  of  delivery  influences  the  need  for  locks.  Where 
only  one  rotation  head  is  run  in  a  lateral,  all  of  which  is  given 
in  turn  to  each  user,  locking  is  not  needed  as  the  taking  of  water 
out  of  turn  can  be  detected.  Locking  would  also  make  neces- 
sary night  ditch  riding  where  changes  are  made  at  less  than  24- 
hour  periods.  Where  several  users  are  taking  water  from  the 
same  lateral  under  continuous-flow  or  demand  methods  it  is  more 
difficult  to  detect  night  raising  of  the  gates  and  locks  may  be 
desirable.  Locks  similar  to  car  seals  have  been  used  in  some 
cases  on  the  Truckee  Carson  project.  These  permit  the  opera- 
tion of  gates  in  cases  of  emergency,  such  as  breaks,  but  leave 
evidence  of  such  operation  when  the  seals  are  broken. 

Locking  of  gates  or  checks  in  the  canals  may  also  be  needed, 
more  usually  on  laterals  than  on  main  canals,  however.  A  turn- 
out can  be  made  to  deliver  extra  water  by  adding  a  flashboard 
in  a  canal  check  and  increasing  the  pressure  on  the  gate.  On 
larger  canals  for  checks  consisting  of  gates  the  difficulties  of 
operation  may  prevent  meddling. 

WINTER  OPERATION 

By  winter  operation  is  meant  the  running  of  water  in  canals 
for  stock  or  domestic  purposes  during  portions  of  the  year  when 


GENERAL  OPERATION  217 

water  is  not  applied  to  the  land.  There  are  some  systems  in  the 
Southwestern  States  where  crops  are  irrigated  practically  through- 
out the  year  and  where  winter  operation  does  not  differ  from  that 
at  other  times.  It  lessens  the  time  available  for  maintenance 
work,  however.  On  some  systems  winter  irrigation  of  orchards 
or  bare  lands  may  be  practised  in  order  to  use  flood  waters  when 
available. 

It  is  usually  advisable  to  shut  water  out  of  canals  as  soon  as 
practicable  in  the  fall  and  not  to  begin  operation,  except  for 
canal  priming,  until  irrigation  is  required  in  the  spring.  In  the 
mountain  States  the  open  weather  available  for  maintenance 
work  may  be  limited  unless  this  is  done.  It  has  been  found  on 
some  systems  that  20  per  cent,  of  the  yearly  diversion  may  take 
place  at  the  beginning  and  end  of  the  operation  seasons  when 
little  actual  irrigation  is  being  given.  Shortening  the  operation 
season  also  reduces  the  time  the  ditch  riders  are  employed. 
Where  a  stream  is  fully  utilized  through  storage,  such  late-  or 
early-season  diversion  may  reduce  the  supply  available  for  the 
main  season.  Where  many  wooden  flumes  are  in  use  it  may  be 
desirable  to  run  water  until  freezing  occurs  in  order  to  prevent 
decay  from  alternate  drying  and  wetting. 

The  need  of  winter  operation  for  stock  use  is  discussed  under 
the  general  question  of  stock  water.  Such  operation,  when  used, 
is  the  lesser  of  two  evils,  the  benefits  to  the  settlers  being  greater 
than  the  disadvantages  to  the  canals.  In  addition  to  the  water 
required  and  prevention  of  canal  cleaning  there  are  the  further 
disadvantages  of  the  cost  of  operation,  actual  injuries  to  the 
canals  and  structures  and  the  greater  additions  to  the  ground 
water  which  may  increase  drainage  needs.  In  some  localities 
muskrats  appear  to  burrow  more  extensively  and  cause  more 
harm  in  canals  operated  during  the  winter. 

In  winter  operation  it  may  not  be  necessary  to  run  water  in 
all  laterals  or  sub-laterals.  Daily  patrolling  may  not  be  needed 
except  at  times  when  ice  is  moving  so  that  the  cost  may  not  be 
high.  Periodic  runs  at  intervals  from  15  to  20  days  may  be  made 
to  replenish  cisterns.  The  proportion  of  the  amount  which  it  is 
necessary  to  turn  into  a  canal  in  order  to  make  such  deliveries 
that  is  actually  used  is  relatively  small  and  the  remainder  will 
largely  reach  the  ground  water  as  seepage.  It  has  been  estimated 
that  winter  operation  on  the  South  Side  Twin  Falls  tract  added 
Y^  acre-foot  per  acre  to  the  ground  water.  Wells  were  very 


218  IRRIGATION  SYSTEMS 

difficult  to  obtain  on  this  area  when  first  irrigated  and  winter 
operation  was  necessary.  At  present,  water  is  being  shut  out  of 
increasing  areas  of  this  system  each  winter  as  wells  are  provided. 
Winter  operation  may  prevent  the  natural  lowering  of  the  ground 
water  during  the  winter  and  add  to  the  resulting  water-logging 
during  the  following  season. 

Where  canals  have  to  be  operated  during  freezing  weather  the 
flow  should  be  kept  uniform  and  at  the  maximum  stage  to  be  run 
while  freezing  takes  place.  After  solid  ice  forms  it  is  not  prac- 
ticable to  increase  the  depth  of  flow  as  pressure  will  be  formed 
under  the  ice  or  water  will  run  over  its  surface,  either  of  which 
may  cause  the  ice  to  break  and  jam  at  structures.  With  metal 
flumes,  the  capacity  will  be  more  largely  reduced  by  freezing 
as  the  ice  forms  around  the  bottom  and  sides  as  well  as  at  the 
surface.  For  very  low  temperatures  it  may  be  difficult  to  oper- 
ate small  metal  flumes  continuously.  Headgates  should  be  ad- 
justed as  much  as  possible  before  freezing  occurs.  To  open  a 
frozen  gate  may  result  in  its  injury.  This  is  equally  or  even  more 
true  of  concrete  structures  than  for  wood. 

When  ice  begins  to  break  and  move,  great  care  is  needed  to 
prevent  jams  at  structures  which  may  act  as  checks  and  force  the 
water  over  the  banks.  If  the  ground  is  also  frozen  the  banks  may 
not  be  eroded  or  may  resist  for  some  time.  At  such  breakups 
the  only  safe  course  is  to  shut  water  out  of  the  canal  until  the  ice 
has  become  soft.  Some  advantage  may  be  secured  by  closing 
the  side  openings  in  checks,  carrying  the  flow  through  the  center 
opening  at  an  increased  velocity. 

Operation  during  freezing  weather  should  be  avoided  where 
possible.  One  Idaho  system  has  found  its  maintenance  cost  to  be 
increased  about  15  cents  per  acre  due  to  the  cost  of  repairs  made 
necessary  by  the  action  of  ice  incident  to  the  running  of  winter 
water. 

COMPLAINTS 

Complaints  are  not  avoidable.  The  delivery  of  water  to 
large  numbers  of  farms  under  the  necessary  conditions  of  ditch 
capacity  and  water  supply  cannot  always  be  carried  out,  even  on 
the  most  carefully  handled  systems,  without  giving  grounds  for 
complaint  in  some  cases.  The  number  and  seriousness  of  such 
complaints  can  be  kept  at  a  minimum  by  well-planned  systems  of 
delivery  and  prompt  attention  to  the  cause  when  complaints  do 


GENERAL  OPERATION  219 

arise.  A  policy  of  operation  which  gives  closer  supervision  to 
delivery  and  a  more  definite  control  of  use  will  reduce  the  number 
of  complaints  due  to  delay  in  time  or  inadequacy  in  amount  of  the 
delivery  of  water.  Such  methods  may  increase  the  expense  of 
operation  and  cause  complaints  on  the  ground  of  cost. 

Complaints  can  be  divided  into  two  general  classes :  those  involv- 
ing questions  of  cost,  and  those  involving  questions  of  service. 
The  methods  of  handling  both  kinds  depend  on  the  form  of  organi- 
zation. With  public  utility  companies  both  rates  and  service  are 
subject  to  public  control.  For  such  companies,  when  rates 
have  been  fixed  or  rules  of  service  prescribed,  the  company  is  to  a 
large  extent  relieved  of  the  responsibility  for  fixing  the  policy  of 
the  system  and  is  responsible  only  for  carrying  it  out.  On 
systems  controlled  by  the  land  owners,  the  general  policies  are 
usually  determined  by  elected  representatives  of  the  users  and  the 
strictly  operation  officials  are  held  for  the  enforcement  of  the 
policies  and  economy  in  expenditures.  Complaints  on  methods 
or  policies  can  be  referred  to  such  elected  officers,  usually  the 
directors.  The  complaints  due  to  costs  can  best  be  answered  by 
keeping  adequate  records  of  expenditures  and  results  so  that 
actual  and  comparative  unit  costs  will  be  known. 

The  complaints  regarding  service  are  generally  due  to  failure 
to  deliver  water  promptly  when  due,  failure  to  get  a  sufficiently 
large  irrigation  head  or  damages  from  breaks.  If  it  is  made 
evident  that  the  whole  force  is  endeavoring  to  give  good  service 
and  that  such  shortcomings  as  do  occur  are  the  result  of  circum- 
stances and  not  of  favoritism,  there  will  be  less  incentive  to  make 
complaints.  The  development  of  a  cooperative  spirit  between 
users  and  officials  is  necessary  for  the  best  results  and  this  can  only 
be  secured  through  the  understanding  of  the-  point  of  view  of  the 
other  that  comes  from  a  familiarity  with  the  conditions  and  diffi- 
culties in  running  both  an  irrigation  system  and  an  irrigated  farm. 

The  methods  of  handling  complaints  should  be  such  as  to  dis- 
courage chronic  or  trivial  kicking  and  still  permit  a  ready  hearing 
and  action  in  reasonable  cases.  The  most  effective  method  of 
eliminating  trivial  or  unreasonable  complaints  is  to  require  that, 
to  be  considered,  all  complaints  must  be  submitted  in  writing. 
This  will  reduce  the  number  received  very  materially,  as  the 
grounds  for  complaint  do  not  look  as  serious  to  many  when  ex- 
pressed in  cold  writing  over  their  signatures  where  assertions 
must  be  definitely  made  and  are  subject  to  verification.  On  some 


220  IRRIGATION  SYSTEMS 

systems  blank  forms  for  complaints  are  used.  These  have  the 
advantage  of  uniformity  and  greater  ease  in  filing.  The  use  of 
such  forms  should  not  prevent  the  consideration  of  written 
reports  if  not  prepared  on  the  form. 

It,  is  also  an  advantage  to  settle  complaints  as  near  to  the 
source  as  possible.  To  " settle  on  the  ditch  bank"  is  good  prac- 
tice. The  handling  of  such  informal  complaints  by  each  ditch 
rider  is  desirable  as  the  remedy  can  be  more  easily  and  quickly 
given  if  the  user  is  in  the  right.  Where  such  adjustments 
cannot  be  made,  appeal  by  written  complaint  to  higher  officials 
should  be  available  to  the  water  user.  When  disputes  between 
the  user  and  ditch  rider  come  to  the  superintendent  with  only  the 
unsupported  statements  of  fact  by  each  on  which  to  make  a 
decision,  it  is  usually  necessary  to  support  the  ditch  rider.  In 
case  this  cannot  be  done  the  rider  should  be  changed. 

On  some  of  the  government  projects  a  grievance  committee 
has  been  found  to  be  an  advantage.  On  these  systems  the  water 
users  are  not  directly  represented  in  the  operation  organization 
and  such  a  committee  becomes  an  arbitration  board  between  the 
users  and  the  officials.  On  cooperative  systems  the  board  of 
directors  is,  in  effect,  such  a  board,  complaints  which  cannot  be 
otherwise  settled  coming  to  the  directors  who  also  have  the 
power  to  act.  The  grievance  committees  on  the  government 
systems  do  not  have  such  powers  to  act;  however,  public  senti- 
ment or  the  willingness  of  the  officials  to  adopt  their  findings  have 
resulted  in  giving  their  conclusions  much  weight  on  some  systems. 

On  the  Twin  Falls  North  Side  canal  red  cards  are  used  for 
complaints  which  are  made  to  the  main  office.  A  rule  is  enforced 
that  all  complaints  must  be  made  within  15  days  of  the  occurrence 
of  the  cause.  This  is  particularly  useful  in  regard  to  claims  for 
rebates  on  charges  due  to  inadequate  service.  The  red  cards  are 
filed  by  ditch-rider  beats  and  furnish  a  general  indication  of  the 
work  of  the  ditch  rider. 

CROP  STATISTICS 

The  crop  statistics  useful  in  the  operation  of  an  irrigation 
system  are  of  two  kinds:  (1)  those  needed  in  the  actual  operation 
of  the  system ;  (2)  those  useful  in  determining  the  financial  con- 
ditions and  progress  of  the  settlers  as  affecting  their  ability  to 
meet  payments  and  the  general  success  of  the  development. 


GENERAL  OPERATION  221 

In  the  first  class  is  included  the  census  of  the  actual  area  irrigated 
in  different  crops  or  types  of  crops.  In  the  second  comes  such 
additional  data  as  the  yields,  average  prices  received,  live  stock 
on  the  farms,,  and  value  of  farms  and  improvements. 

Where  rotation  methods  of  delivery  on  the  basis  of  a  definite 
time  schedule  are  used  it  is  necessary  to  know  the  area  to  be  irri- 
gated in  each  kind  of  crop  on  each  farm  in  order  to  plan  such 
schedules.  Similar  information  is  needed  to  properly  handle 
delivery  on  demand  if  the  rights  are  proportional  to  the  areas 
irrigated.  With  continuous  delivery  such  data  are  very  useful, 
particularly  in  times  of  scarcity  of  water  as  the  areas  of  the  more 
valuable  crops  can  be  given  preference.  Many  systems  now 
collect  data  in  the  spring  on  the  acreage  of  each  crop  which  will 
be  irrigated  on  each  farm  during  the  coming  season.  This  may 
be  done  by  the  ditch  riders  in  advance  of  the  season  or  by  re- 
quiring each  land  owner  to  file  with  the  company  a  statement  or 
application  for  water  during  the  coming  season  in  which  such 
data  is  given.  Such  applications  may  be  made  a  prerequisite  of 
the  right  to  receive  service.  These  statistics  furnish  data  on 
acreage  only  and  give  no  information  on  yields  or  profits. 

The  form  used  by  the  Turlock  irrigation  district,  in  collecting 
such  data,  is  shown  in  Fig.  8,  page  115.  These  are  bound  in 
duplicate,  the  original  on  white  paper  and  the  carbon  on  yellow. 

With  some  forms  of  organization  a  more  elaborate  census  may 
be  taken  at  the  end  of  the  irrigation  season.  The  most  complete 
of  these  are  those  taken  by  the  U.  S.  Reclamation  Service. 
There  is  little  doubt  as  to  the  value  of  such  data  in  comparing 
conditions  and  progress  from  year  to  year  if  the  data  are  properly 
compiled  and  analyzed.  There  may  be  considerable  question, 
however,  as  to  whether  the  value  of  such  a  census  to  the  land 
owners  is  as  large  as  the  value  to  the  operation  organization.  The 
operation  organization  is  in  a  position  to  secure  such  data  effect- 
ively as  the  ditch  riders  are  familiar  with  each  farm  in  their  beat 
and  can  make  the  census  economically  during  the  less  busy  period 
at  the  end  of  the  operation  season.  The  chief  value  of  any  such 
data  is  local  with  each  system;  comparisons  of  averages  between 
different  systems,  as  a  whole,  are  of  little  use  owing  to  the  varia- 
tions of  conditions  which  always  occur.  On  many  large  sys- 
tems soil  and  other  conditions  vary  widely  on  different  portions 
of  the  project.  For  such  conditions,  the  crop  census  can  be  very 
useful  in  giving  data  on  the  average  conditions  of  the  land  owners 


222 


IRRIGATION  SYSTEMS 


DEPARTMENT   OF   THE    INTERIOR 

UNITED    STATES    RECLAMATION    SERVICE 
WATER    USER    CENSUS 


tt 

W 

3 

c* 

w 

w 

Name 

Address 

Owner  or  renter? 

Previous  occupation 

Previous  location 

Date  of  settlement 

Number  of  people  on  farm 

Years  experience  in  humid  farming                              ;in  irrigation  farming 

tf 
< 

u, 

u 

£ 

l- 

Subdivision                                Sec 

T.             R.                  M. 

Subdivision                                Sec.             T.             R.                 M. 

Subdivision                               Sec.            T.            R.                 M. 

Acres  in  farm,  total                       ; 

irrigable                            ;seeped                          Drained 

Acres  cleared  and  leveled 

;cost  per  acre  of  clearing  and  leveling  $ 

Total  cost  of  all  other  improvements  $ 

Purchase  price  of  farm  without  improvements  8 

Present  value  of  farm  with  improvements  2 

THE  STOCK  &  EQUIPMENT 

KIND 

NUMBER 

VALUE 

Horses, 

5 

Mules 

Cattle 

Sheep 

Hogs 

Fowls 

Hives  of  Bees 

Total  

$ 

Equipment  „  

Grand  Total           

$ 

10 

6 

a 
U 

w 
K 
t- 

In  listing  crops  (other  side):  under  BEANS  include  •white  and  brown  beans  raised  for  market 
for  human  food;  under  CANE  include  sugar  and  sorghum  canes:   under  CORN.   INDIAN,  in- 
clude all  varieties  of  Indian  field  corn;  under  CORN.  SORGHUM,  include  the  Sorghum  fam- 
ily, such  as  Kaffir  corns,  Milo  maize,  Jerusalem  corn  and  Egyptian  rice  corn,  raised  for  grain: 
under  CORN,  FODDER,  include  stover  or  fodder  harvested  either  from  Indian  or  Sorghum 
corns;  under  FRUITS.  SMALL,  include  berries,  currants,  grapes,  cherries,  plums,  olives,  dates 
and  figs;  under  GARDEN,  include  the  family  garden  and  all  truck  crops  grown  for  market  and 
not>  given  in  the  printed  list;  under  PEAS,  include  all  threshed  field  peas,  soy-beans,  cow-peas 
and  the  like:  under  WHEAT  include  all  common  wheats,  macaroni  wheats,  spelt  and  emmer 
raised  for  grain;  under  EACH  CROP  include  any  acreage  on  which  the  crop  faUed  and  com- 
pute the  average  yield  from  the  total  acreage  of  the  crop. 

REMARKS 


Water  User  or  Riter 

FIG.  27a. 
FIGS.  27a  and  6. — Form  for  crop  census  used  by  U.  S.  Reclamation  Service. 


GENERAL  OPERATION 


223 


Kind 

Acres 

YIELD 

VALUE 

Dni 

Per  Acre 

Total 

Per  Unit 

Per  Acre 

Total 

Alfalfa  Hay 

ton 

$ 

$ 

S 

Alfalfa  Seed 

bu 

Apples 

Ib. 

Barley 

bu 

Beans 

bu 

Beets.  Sugar 

ton 

Cane 

ton 

Clover  Hay 

ton 

Clover  Seed 

bu 

Corn,  Indian 

bu. 

Corn.  Sorghum 

bu. 

Corn,  Fodder 

ton 

Cotton 

Ib. 

Flax 

bu. 

Fruits,  Citrus 

Ib. 

Fruits.  Small 

Ib. 

Garden 

— 







Hay* 

ton 

Hops 

Ib. 

Millet  Seed 

bu. 
bu. 

Oats 

Onions  t 

bu. 

Pasture 

_ 

_  





Peaches 

Ib. 

Pears 

Ib. 
bu. 

Peas 

Prunes 

Ib. 

Potatoes.  C.  » 

bu. 

Potatoes,  S.  § 

bu. 

Rye 

bu. 

Wheat 

bu. 

Miscellaneous 

Total  acreage 


Less  acreage 
counted  twice 


Net  acreage 
cropped 


Total  Value 


Average  Value  per  Acre 


*  Except  alfalfa  and  clover  hay. 
t  Onions  raised  for  market. 

*  Common 
i  Sweet 


Total  irrigated 
acreage  of: 


Non-bearing  orchard 
Young  alfalfa  (no  crop) 
Ground  fall-plowed 
Miscellaneous 

Total 


Less  acreage  of  crops  grown  in  non-bearing  orchard, 
young  alfalfa  ground  fall-plowed,  etc. 

Net  area  irrigated  without  crop 

Net  acreage  cropped  (See  above)  _ 

Total  irrigated  acrenge 

FIG.  276. 


224  IRRIGATION  SYSTEMS 

in  the  different  divisions  which  may  be  used  as  a  basis  of  adjust- 
ment of  payments,  either  in  time  or  in  amount. 

The  5X8  card  used  by  the  U.  S.  Reclamation  Service  for  col- 
lecting such  statistics  is  shown  in  Fig.  27.  This  is  a  general  form 
for  use  on  all  projects  and  consequently  contains  more  items 
than  would  be  required  for  any  single  system.  The  omission  of 
the  items  not  desired  on  other  systems  will  enable  the  size  of  the 
form  to  be  reduced.  If  a  copy  of  each  card  is  given  to  the  land 
owner  a  form  using  only  one  side  of  the  sheet  enables  carbon 
copies  to  be  made  and  is  preferable. 

The  expense  of  taking  a  complete  agricultural  census  need  not 
be  high.  Where  the  one  collecting  the  data  is  familiar  with  the 
area  covered  returns  from  an  average  of  20  farms  per  day  should 
be  secured  in  the  field.  If  many  trips  over  the  area  are  required 
in  order  to  find  those  missed  at  earlier  calls  the  average  may  be 
less  than  this.  A  personal  visit  is  essential  if  complete  data  are 
to  be  secured.  Inquiries  through  the  mail  will  not  ordinarily 
bring  replies  from  over  30  to  40  per  cent,  of  those  addressed. 
Proper  follow-up  letters  may  materially  increase  this  per- 
centage, but  many  of  the  replies  received  will  be  incomplete  and 
not  on  a  uniform  basis. 

Where  such  a  detailed  census  is  not  considered  warranted,  it 
may  be  possible  to  secure  data  regarding  particular  crops  from 
other  sources.  The  beet-sugar  companies  keep  quite  complete 
records  of  all  lands  under  contract  to  raise  beets.  Various  mar- 
keting organizations  may  have  similar  records  for  the  crops 
which  they  handle.  If  the  areas  of  each  crop  irrigated  have  been 
secured  in  the  spring,  the  average  yields  may  be  secured  in  the 
fall  by  a  canvas  of  a  selected  number,  such  as  75  or  100  of 
individual  farms,  the  average  yield  of  which  is  assumed  to  be 
typical. 

Where  financial  returns  are  secured  in  the  census,  it  is  cus- 
tomary to  apply  a  uniform  unit  price  to  each  crop.  This  is 
desirable  for  such  staple  crops  as  alfalfa  or  grain.  For  special 
crops  such  as  fruits  the  actual  prices  for  each  farm  may  be  used. 

The  interest  which  the  canal  organization  has  in  such  records 
depends  on  the  form  or  organization  and  stage  of  development  of 
the  system.  Where  land  and  water  have  been  sold  on  long-time 
payments,  the  organization  carrying  such  deferred  payments  has 
a  very  material  interest  in  the  progress  in  development  of  the 
land  owner  as  the  securing  of  their  payments  is  dependent  mainly 


GENERAL  OPERATION  225 

on  the  earnings  of  the  land.  Where  the  system  is  owned  directly 
by  the  land  owners,  such  as  in  cooperative  companies  or  irrigation 
districts,  such  data  may  have  much  value  in  securing  loans  or  in 
selling  bonds  for  improvements,  those  systems  which  are  able  to 
show  a  regular  progress  in  development  and  increase  in  resources 
of  the  land  owners  furnishing  a  better  security  for  such  loans. 
Where  such  data  are  collected  for  the  use  of  the  land  owners 
rather  than  in  canal  operation,  the  census  may  be  taken  by  the 
canal  organization  with  their  regular  force  due  to  their  familiarity 
with  the  conditions. 

DRAINAGE 

Drainage,  either  partial  or  complete,  is  coming  to  be  recog- 
nized as  a  usual  necessity  on  the  majority  of  irrigation  systems. 
Where  the  boundaries  of  the  drained  area  are  included  within  or 
coincide  with  those  under  an  irrigation  system  the  operation  and 
maintenance  of  the  drains  may  be  handled  by  the  irrigation 
organization. 

In  most  cases  drainage  systems  are  built  and  maintained  by 
district  organizations  separate  from  those  handling  the  irrigation 
system.  The  U.  S.  Reclamation  Service,  irrigation  districts  in 
some  States  and  a  few  private  systems  build  and  operate  the 
drains  needed  with  the  same  organization  used  for  the  irrigation 
system.  As  drains  are  not  usually  constructed  until  actually 
needed,  the  construction  comes  after  the  irrigation  system  is 
completed  and  in  use.  The  construction  of  drains  on  private 
systems,  either  for  surface  waste,  deep  drainage  or  both  may  be 
more  largely  as  an  aid  in  selling  land  than  as  a  direct  part  of  the 
irrigation  system. 

On  Carey  Act  projects,  drainage,  when  required,  has  usually 
been  handled  by  separate  drainage  district  organizations.  If 
such  districts  include  much  unpatented  land  the  security  behind 
the  drainage  bonds  is  less  desirable.  With  Carey  Act  projects  the 
price  for  the  construction  of  the  irrigation  system  is  fixed  in  the 
contract  between  the  company  and  the  State.  The  terms  of  this 
contract  can  be  fixed  for  the  irrigation  system  as  the  work  to  be 
done  can  be  definitely  specified ;  for  drainage,  however,  the  extent 
of  the  work  to  be  done  cannot  be  determined  until  needed  follow- 
ing the  actual  use  of  water. 

Drainage  systems  may  be  built  for  smaller  units  of  area  than 
that  of  the  irrigation  system  as  only  certain  parts  of  the  lands 

15 


226  IRRIGATION  SYSTEMS 

'may  be  injured.  The  area  of  a  drainage  district  usually  in- 
cludes only  the  land  tributary  to  a  certain  outlet.  There  may  be 
several  such  outlets  within  an  irrigation  system.  Drainage  dis- 
trict costs  are  required  by  law  to  be  assessed  on  the  basis  of  the 
benefit  to  the  land  in  nearly  all  cases.  Where  only  a  part  of  the 
area  under  a  canal  is  injured,  only  such  lands  can  be  included  in 
the  drainage  district.  Higher  lands  whose  deep  percolation 
losses  may  be  the  cause  of  the  injury  are  not  made  to  pay  for  the 
costs  of  the  drainage  district.  For  such  cases  the  building  of  the 
drains  by  the  irrigation  system  as  a  whole  as  is  done  within 
irrigation  districts  in  California  or  on  some  government  systems 
is  a  fairer  distribution  of  the  cost. 

Drainage  water  comes  from  canal  seepage,  surface  waste  in 
irrigation  and  deep  percolation  of  part  of  the  water  applied  to  the 
land.  The  only  one  of  these  which  comes  directly  from  the  canal 
system  and  for  which  it  may  be  responsible  is  the  canal  seepage. 
The  conditions  under  which  a  canal  company  may  be  held  re- 
sponsible for  such  seepage  have  been  discussed  under  the  head 
of  damages  in  Chapter  I.  The  deep  percolation  loss  on  irrigated 
fields  is  frequently  a  considerable  percentage  of  the  amount 
applied  and  such  percolation,  in  many  cases,  is  the  principal  cause 
of  the  rise  of  ground  water.  The  extent  of  such  field  losses  is  not 
usually  as  fully  realized  or  understood  by  the  users  as  the  loss 
from  the  canals,  so  that  the  canals  are  blamed  for  drainage 
troubles  for  which  they  may  be  only  partly  responsible. 

The  operation  organization  may  be  of  assistance  in  restricting 
the  need  for  drainage  by  their  influence  and  control  over  the  use 
of  water  in  irrigation.  Where  the  systems  are  still  unpaid  for 
and  are  operated  by  the  constructing  organizations,  the  interest 
of  such  organizations  is  greater  than  the  mere  saving  of  the  cost 
of  drainage.  Land  needing  drainage  is  not  in  condition  to  earn 
the  payments  for  the  irrigation  system.  Assistance  in  drainage 
may  be  necessary  in  order  to  protect  the  irrigation  payments. 

Possible  future  drainage  should  be  kept  in  mind  when  the  loca- 
tion of  the  irrigation  canals  is  planned.  The  use  of  natural  drain- 
age channels  for  canals  will  interfere  with  both  surface  runoff  and 
the  construction  of  drains. 

Maintenance  is  as  essential  for  drainage  systems  as  for  canals. 
The  effect  of  open  drains  depends  on  the  height  of  the  water  in 
the  drain  for  a  given  flow.  If  the  drain  becomes  silted  or  the 
growth  of  vegetation  raises  the  water  surface  the  effect  of  the 


GENERAL  OPERATION  227 

drain  is  lessened.  In  the  slower  velocities  usual  in  drains,  the 
condition  for  growth  of  moss,  pond-weed,  tules,  or  other  forms 
of  vegetation  are  favorable  and  cleaning  or  cutting  during  the 
irrigation  season  will  probably  be  required.  The  methods  of  re- 
moval of  such  vegetation  are  similar  to  those  used  in  canals. 
The  sloughing  of  side  slopes  or  silting,  due  to  deposits  washed 
in  or  picked  up  in  the  drain,  may  make  periodic  dredging  or 
cleaning  necessary. 

Drains,  particularly  covered  ones,  should  not  be  used  for  sur- 
face waste  in  irrigation.  This  is  particularly  true  for  small  lat- 
eral drains.  The  use  of  such  drains  to  carry  the  full  irrigating 
head  of  a  farm  has,  in  some  cases,  resulted  in  washing  in  sufficient 
matter  to  clog  the  drain. 

DELIVERY  OF  STORAGE  THROUGH  STREAMS 

With  the  more  complete  utilization  of  stream  flow  by  means  of 
storage,  the  administration  of  many  Western  streams  has  become 
quite  complicated.  The  division  of  water  from  a  large  and  long 
main  canal  to  the  various  laterals  presents  many  problems  if  the 
result  is  to  be  equitably  accomplished.  Such  canals,  however, 
are  subject  to  control  as  to  the  total  flow  and  the  rights  of  the 
users  under  the  different  laterals  are  generally  equal  in  time  and 
amount.  The  distribution  of  water  from  a  stream  to  the  various 
canal  systems  along  its  course  is  similar  to  the  division  within 
each  system  but  is  without  the  advantage  of  control  of  the  total 
flow  or  uniformity  of  priority.  If,  in  addition,  the  return  flow  is 
of  appreciable  amount,  the  result  is  a  condition  which  requires 
an  understanding  of  the  characteristics  of  the  particular  stream 
and  of  river  hydrography,  if  all  canals  are  to  receive  the  water 
to  which  they  are'entitled. 

The  administration  of  the  diversions  from  streams  is  under  the 
supervision  of  the  State  engineer  in  most  of  the  States.  The 
extent  to  which  such  supervision  is  carried  out  varies  in  the  differ- 
ent States.  Such  State  administration  can  have  effect  only  where 
the  rights  of  the  different  canals  both  as  to  amount  and  as  to 
priority,  have  been  adjudicated.  The  extent  of  the  administra- 
tion exercised  by  the  state  may  not  be  sufficient  for  the  needs  of 
some  more  highly  utilized  streams  and  a  combination  of  the 
canals  may  be  effected  to  supplement  such  control.  This  has 
been  done  on  the  Arkansas  River  in  Colorado.  Where  no  direct 


228  IRRIGATION  SYSTEMS 

procedure  for  the  determination  of  all  rights  on  a  stream  has 
been  provided  by  law,  the  canals  may  enter  into  a  controlling  and 
binding  agreement  adopted  mainly  by  mutual  consent,  such  as 
the  present  control  of  the  Yakima  River  in  Washington. 

The  distribution  of  direct  flow  does  not  present  such  complica- 
tions as  does  the  mixture  of  direct  flow  and  storage  rights. 
Where  a  canal  system  can  procure  storage  along  its  canal  and 
below  its  diversion  point,  the  condition  is  mainly  that  of  direct 
use.  When,  however,  the  storage  for  lower  canals  is  provided 
on  the  upper  drainage  area  above  the  diversion  points  of  inter- 
vening canals,  the  conveyance  of  such  water  to  the  canal  entitled 
to  its  use  is  a  difficult  matter.  The  laws  of  the  different  States 
permit  the  use  of  natural  stream  channels  for  the  conveyance  of 
such  stored  water.  The  one  owning  the  storage  is  entitled  to 
release  such  water  at  his  desire,  let  it  mingle  with  the  natural 
flow  and  be  conveyed  through  the  stream  to  his  point  of  diversion 
and  there  divert  the  amount  of  such  storage  less  the  loss  of  con- 
veyance in  the  stream  channel.  Water,  when  stored,  is  reduced 
to  ownership  and  such  storage  water  is  not  subject  to  being  taken 
by  earlier  rights  when  being  conveyed  through  the  stream.  The 
owner  of  the  storage  is  liable  only  for  such  injury  as  may  be 
caused  to  earlier  rights  by  such  flow.  As  such  storage  is  released 
at  low  stages  of  the  river  such  additional  flow  may  benefit  rather 
than  injure,  due  to  the  increase  in  the  river  stage,  thus  making 
diversion  of  the  natural  flow  less  difficult.  The  losses  in  convey- 
ance are  usually  determined  for  each  stream  although  definite 
determination  is  difficult.  The  statutes  of  Arizona  provide  that 
a  loss  of  ^2  per  cent,  per  mile  of  stream  used  shall  be  deducted. 
In  some  streams  there  may  be  a  gain  due  to  return  flow  and  the 
loss  in  conveyance  may  be  quite  small. 

Although  the  legal  questions  as  to  the  relative  rights  on  a 
stream  may  be  quite  definite,  the  physical  questions  as  to  which 
water  is  natural  flow  and  which  is  storage,  and  the  actual  detec- 
tion or  proof  of  excess  diversion  by  intermediate  ditches  are  ones 
of  much  difficulty.  Increasing  the  flow  of  a  stream  due  to  the 
release  of  storage  has  a  similar  effect  on  the  diversion  by  canals 
that  an  increase  in  the  flow  in  a  lateral  has  on  the  turnouts. 
Unless  the  headgates  are  lowered  the  increased  flow,  which  in- 
creases the  depth  or  head  on  the  headgates,  will  increase  the 
amount  diverted  at  the  expense  of  the  stored  water  being  run. 
If  there  are  a  sufficient  number  of  such  headgates  to  be  passed, 


GENERAL  OPERATION  229 

the  storage  flow  may  be  seriously  depleted.  Such  lowering  of 
headgate's  may  be  objected  to  by  their  owners  and  can  be  done 
only  by  those  acting  under  the  police  authority  of  the  State, 
such  as  water  commissioners,  of  the  State  engineer  or  of  the 
courts.  The  expense  of  such  administration  is  borne  by  those 
benefited.  Some  of  the  older  systems  may  control  the  flow  into 
their  canals  at  low  water  by  means  of  brush  or  other  forms  of 
temporary  dams  without  permanent  headgates.  For  adjudi- 
cated rights  permanent  headgates  are  generally  required  as  a 
prerequisite  to  the  right  to  receive  the  amount  of  their  adjudi- 
cated right. 

Water  released  from  storage  blends  with  the  natural  flow.  A 
sharp  increase  in  the  flow  at  the  reservoir  will  flatten  out,  the 
increase  at  points  lower  down  on  the  stream  being  gradual  and 
less  marked.  If  there  are  tributaries,  which  may  have  a  variable 
discharge,  entering  the  stream  below  the  reservoir,  or  if  the  rate  of 
return  flow  is  of  material  amount,  the  separation  of  natural  flow 
and  storage  cannot  be  made  exactly.  Even  with  complete  records 
of  inflow  at  all  the  points  the  complications  of  time  allowance  for 
the  various  effects  to  be  felt  at  any  point  will  render  the  resulting 
estimate  subject  to  uncertainty.  If  complete  records  are  avail- 
able for  the  stream  before  storage  is  released  and  also  after  a  few 
years  of  use  for  the  conveyance  of  storage,  the  administration  of 
the  stream  can  be  developed  from  the  experience  acquired  in 
handling  it. 

Storage  both  on  the  watershed  and  adjacent  to  the  irrigated 
areas  has  been  extensively  developed  in  northeastern  Colorado. 
In  some  cases  a  canal  system  may  own  a  reservoir  site  below  the 
level  of  the  lands  which  they  serve.  A  system  of  exchanging 
water  has  been  developed,  the  water  to  which  earlier  direct-flow 
rights  lower  on  the  stream  are  entitled  being  diverted  by  such 
higher  canals  and  an  equivalent  amount  of  the  storage  released 
for  use  by  the  earlier  rights.  Such  exchanges  are  carried  on  ex- 
tensively and  have  resulted  in  the  very  complete  use  of  such 
streams.  The  handling  of  the  exchanges  is  under  the  supervision 
of  the  water  commissioner  of  the  State. 

On  the  Snake  River  storage  has  been  provided  at  Jackson 
Lake  in  Wyoming  for  use  by  some  of  the  more  recent  systems  in 
the  vicinity  of  Twin  Falls,  including  the  Minidoka  project  of  the 
government.  Much  controversy  with  the  older  canals  on  the 
upper  Snake  River  has  arisen  over  the  conveyance  of  the  storage 


230  IRRIGATION  SYSTEMS 

water  past  their  diversions.  Similar  conditions  have  arisen  on 
the  upper  South  Platte  River  in  Colorado,  and  others  and  will 
probably  arise  in  an  increasing  number  of  streams  as  the  construc- 
tion of  storage  increases. 

OPERATION  OF  LARGE  PUMPING  PLANTS 

The  use  of  pumping  plants  for  relatively  large  areas  is  a  de- 
velopment of  recent  years  which  has  been  due  to  the  increase  in 
the  value  of  water  and  land  and  to  the  decrease  in  the  cost  of 
power.  It  is  also  partly  due  to  the  improvement  in  the  char- 
acter of  pumping  equipment  used  with  the  resulting  increase  in 
efficiency. 

While  the  operation  of  irrigation  systems  supplied  from  pump- 
ing is  generally  similar  to  that  of  gravity  supplies,  certain  ele- 
ments in  the  cost  of  operation  make  it  necessary  to  plan  the 
delivery  methods  somewhat  differently  where  pumped  water  is 
used.  The  following  discussion  does  not  attempt  to  cover  ques- 
tions of  construction  or  of  mechanical  operation. 

Pumping  systems  irrigating  sufficient  area  to  require  the  serv- 
ices of  an  operation  organization  usually  secure  their  water  by 
pumping  from  surface  sources.  In  conveying  water  from  a 
stream  to  lands  adjacent  to  and  higher  than  the  adjoining  stream 
two  methods  may  be  used.  A  canal  may  be  run  on  grade  con- 
tour from  the  river  sufficiently  high  to  cover  the  land  or  the  water 
may  be  pumped  directly  from  the  stream.  The  cost  of  construc- 
tion and  operation  of  the  diversion  canal  can  be  compared  with 
the  similar  costs  of  the  pumping  lift.  For  streams  having  flat 
gradients  or  for  locations  where  the  diversion  canal  passes  through 
difficult  country,  the  pumping  plant  may  be  cheaper.  That  such 
conditions  do  occur  is  evidenced  by  the  number  of  such  pumping 
plants  which  have  been  installed. 

Canal  Operation  under  Pumping  Plants. — The  generally  higher 
cost  of  pumped  water  tends  to  its  more  economical  use.  The 
heads  delivered  for  irrigation  to  each  farm  should  be  those  which 
can  be  most  efficiently  handled.  This  makes  the  use  of  rotation 
delivery  more  general.  Where  continuous  flow  gives  an  efficient 
use  of  water  it  will  also  furnish  a  relatively  uniform  load  on  the 
pumping  plants.  Delivery  on  demand  is  not  desirable  as  it  tends 
to  a  high  peak  use  and  a  less  constant  load.  Where  rotation  is 
to  be  used  and  the  delivery  heads  are  relatively  large  in  propor- 


GENERAL  OPERATION  231 

tion  to  the  capacity  of  the  pumping  stations,  the  capacity  of  the 
units  should  be  selected  so  that  the  station  output  can  be  varied 
by  multiples  of  the  rotation  heads. 

For  canal  systems  supplied  by  pumping  the  cost  of  service  is 
more  nearly  proportional  to  the  quantity  of  water  handled  than 
to  the  acreage  served.  For  gravity  supplies  the  acreage  served 
is  generally  the  controlling  element  of  cost.  Pumping  systems 
resemble  those  supplied  by  storage  in  that  the  cost  may  be  more 
largely  that  of  developing  the  water  supply  rather  than  the  cost 
of  its  conveyance  and  distribution.  This  condition  makes  the 
use  of  the  quantity  basis  for  charges  even  more  desirable  for 
pumping  systems  than  for  gravity  supplies. 

For  gravity  systems  water  may  be  diverted  into  the  canals 
and  if  not  used,  wasted  with  but  little  direct  loss  or  expense. 
With  pumped  water  this  is  not  the  case,  as  each  acre-foot  of 
water  pumped  into  the  canals  represents  an  actual  cost  for  pump- 
ing. A  closer  control  of  the  water  and  supervision  of  its  distribu- 
tion arid  use  is  required  in  such  cases. 

It  is  essential  that  the  pumping  season  be  restricted  in  length 
where  power  is  purchased  under  a  minimum  monthly  rate  for 
each  month  of  use.  The  cost  of  attendance  is  also  an  added 
factor.  This  makes  it  undesirable  to  attempt  to  deliver  stock 
water  or  to  winter  operate  pumping  plants. 

Where  rates  for  power  are  based  either  wholly  or  partly  on  the 
maximum  demand  or  on  the  connected  load,  it  is  important  that 
the  peak  demand  be  reduced  to  a  minimum.  This  also  results 
in  a  saving  in  equipment.  This  can  be  done  if  the  crops  grown 
are  diversified  so  that  their  periods  of  demand  do  not  coincide, 
or,  if  deep-rooted  crops,  particularly  orchards,  are  irrigated  in 
which  the  seasonal  demand  for  water  is  more  uniform.  The  peak 
demand  may  be  reduced  by  the  form  of  rates  for  water.  The 
charge  for  water  may  be  made  lower  during  the  periods  of  less 
demand  in  order  to  encourage  use  then  and  reduce  the  needs  at 
the  height  of  the  season.  The  maximum  rate  of  demand  can  be 
made  a  part  of  the  water-right  contract,  such  as  the  agreement 
for  the  delivery  of  1  second-foot  to  a  relatively  large  area.  W^here 
the  water  rights  are  based  on  the  use  of  a  certain  number  of  acre- 
feet  per  acre  for  the  season  the  maximum  amount  which  can  be 
taken  in  any  one  month  may  be  specified  such  as  a  right  to  2j-£ 
acre-feet  per  acre  per  season  not  over  J£  acre-foot  of  which  is  to 
be  used  in  any  one  month. 


232  IRRIGATION  SYSTEMS 

Equipment  of  Pumping  Plants. — In  order  to  operate  each  pump 
efficiently,  the  number  of  units  in  a  station  should  be  sufficient 
so  that  the  variations  in  discharge  can  be  obtained  by  operating 
varying  numbers  of  pumps  rather  than  by  varying  the  discharge 
of  each  pump.  Usually  at  least  three  units  will  be  desirable  for 
larger  stations  although  some  plants  have  been  built  with  two, 
one  of  which  has  a  capacity  about  twice  that  of  the  other.  Larger 
units  have  somewhat  higher  efficiencies  although  for  sizes  above 
12  or  15  inches  for  centrifugal  pumps  such  increases  are  relatively 
small.  It  may  be  desirable  to  have  an  extra  unit  for  emergency 
use.  This  may  not  be  necessary,  however,  as  with  four  or  more 
units  one  can  be  shut  down  without  material  injury  except  at 
the  short  maximum  peak  of  the  season. 

Foot  valves  or  other  sources  of  loss  of  head  should  be  avoided. 
For  higher  lifts  a  check  valve  in  the  discharge  pipe  is  used,  to 
protect  the  pump  casing  from  surges  when  the  pump  is  shut  down. 
Valves  are  relatively  more  important  on  low  lifts  as  the  loss  caused 
is  a  greater  percentage  of  the  useful  work  accomplished. 

Where  the  head  pumped  against  does  not  vary  the  pumps  can 
be  direct-connected  to  motors  if  they  are  designed  for  the  same 
speed.  Where  the  head  varies  during  the  season  or  in  different 
seasons  belt  connection  may  be  used  so  that  the  speed  of  the 
pump  can  be  adjusted  to  the  lift.  Such  variations  are  more  usual 
in  pumping  from  wells.  The  variations  that  occur  in  the  stages  of 
rivers  from  which  water  may  be  pumped  may  also  be  of  impor- 
tance. For  high  lifts  such  variations  are  of  less  relative  impor- 
tance and  it  may  not  be  necessary  to  change  the  speed.  In  one 
plant  provision  has  been  made  for  changing  the  pump  runners 
during  the  season  due  to  variations  in  the  head  of  about  40  per 
cent,  in  a  low-lift  plant.  For  the  ordinary  changes  of  head,  two- 
speed  motors  or  belt  connection  with  change  of  speed  secured  by 
changing  the  sizes  of  the  pulleys  might  be  preferable. 

Operation  of  Pumping  Plants. — Power  consumption  is  most 
readily  expressed  in  terms  of  kilowatt-hours  used  per  acre-foot  of 
water  lifted  through  a  height  of  1  foot  or  per  foot  acre-foot.  For 
100  per  cent,  efficiency  1.025  kilowatt-hours  would  be  required  per 
foot  acre-foot.  In  practice,  some  plants  have  secured  a  foot  acre- 
foot  per  1.7  kilowatt-hours  of  power  input  equivalent  to  an  over- 
all efficiency  of  60  per  cent.  Small  individual  pumping  plants 
may  require  as  much  as  3  kilowatt-hours  or  an  overall  efficiency 
of  34  per  cent.  For  well-built  and  maintained  plants  serving 


GENERAL  OPERATION  233 

areas  of  over  500  acres  not  over  2  kilowatt-hours  per  foot  acre- 
foot  should  be  needed.  This  is  equivalent  to  about  50  per  cent, 
overall  efficiency. 

Continuous  attendance  is  customary  at  larger  plants.  Where 
a  series  of  lifts  are  located  a  short  distance  apart  one  operator  may 
attend  to  more  than  one  plant.  When  continuous  attendance  is 
used,  large  units  are  more  economical  in  labor  cost.  In  some 
cases  the  operator  may  patrol  a  portion  of  the  adjacent  canal. 
Whether  continuous  attendance  is  used  or  not,  the  plants  should 
be  equipped  with  protective  devices  for  such  conditions  as  no 
voltage  and  be  made  as  nearly  automatic  as  possible.  Two  shifts 
of  12  hours  each  or  three  of  8  hours  each  may  be  used,  the  former 
being  more  usual  except  on  government  systems. 

In  some  systems  small  pumping  plants  for  lifting  water  to  cover 
higher  areas  or  for  drainage  of  small  areas  may  be  used,  their 
operation  being  handled  by  the  general  operation  force.  These 
plants  are  usually  small  and  comparable  with  those  used  for 
individual  land  owners.  Attendance  is  not  continuous  with  such 
plants  and  they  should  be  planned  to  operate  as  nearly  automat- 
ically as  possible.  It  is  often  preferable  to  arrange  with  adja- 
cent land  owners  to  give  such  routine  attention  for  oiling  as  may 
be  needed  rather  than  to  use  any  of  the  regularly  employed  force. 
For  such  plants  electricity  is  preferable  due  to  the  smaller  amount 
of  attention  needed. 

Source  of  Power. — Electric  power  is  used  by  the  greater  num- 
ber of  large  irrigation  pumping  plants.  The  rates  under  which 
this  is  secured  vary  both  in  character  and  amount.  In  some  cases 
the  power  is  generated  by  the  irrigation  companies ;  more  usually 
it  is  secured  from  the  larger  power  systems.  Three  general  kinds 
of  rates  for  power  are  used:  the  flat  rate,  the  meter  rate  with  a 
certain  minimum  and  a  meter  rate  plus  a  certain  demand  charge. 
With  all  forms  of  rates  it  is  desirable  to  keep  the  connected  load 
as  small  as  practicable.  This  is  particularly  important  with  the 
flat  rate.  The  usual  flat  rates  vary  from  $25  to  $40  per  horse- 
power for  6-month  season.  Other  typical  rates  would  be  about 
$12  to  $18  per  horsepower  demand  charges  for  6  months  service 
plus  an  energy  charge  of  about  J£  cent  per  kilowatt-hour. 
Where  a  meter  rate  with  minimum  charges  is  used,  the  meter  rate 
for  larger  plants  varies  from  less  than  1  to  2  cents  per  kilowatt- 
hour  depending  on  the  size  of  the  plant  and  the  load  factor  plus  a 
monthly  minimum  of  $1  to  $2  per  horsepower.  One  kilowatt 


234  IRRIGATION  SYSTEMS 

equals  1.34  horsepower.  In  some  cases  lower  rates  may  be  made 
for  use  during  19  or  20  hours  per  day,  the  pumps  being  shut  down 
during  the  lighting  load  peak  in  the  evening.  For  medium-size 
plants  the  saving  in  rates  may  be  sufficient  to  warrant  such  opera- 
tion; for  large  systems  the  disadvantages  in  canal  operation  will 
overbalance  the  saving  in  power  cost. 

In  some  cases  an  irrigation  system  may  be  able  to  generate 
power  at  its  diversion  dam  or  at  drops  in  its  canals.  The  Mini- 
doka  project  develops  sufficient  power  at  its  dam  to  pump  water 
for  about  50,000  acres.  Drops  are  utilized  on  several  systems, 
among  them  the  Sunnyside  and  Huntley  projects,  for  pumping  a 
portion  of  the  water  to  higher  elevations.  Power  generated  at 
drops  has  a  seasonal  characteristic  similar  to  that  of  irrigation 
pumping  and  can  be  used  very  advantageously  for  such  purposes. 
Where  the  drop  is  located  at  the  point  at  which  it  is  desired  to 
pump,  direct  connection  of  turbine  and  pump  may  be  made. 

Where  power  is  generated  at  diversion  or  storage  dams,  the 
irrigation  system  may  also  carry  on  a  general  power  business. 
This  can  be  done  directly  or  by  leasing  to  other  power  companies. 
Such  power  business  may  be  under  the  general  supervision  of 
the  manager  of  the  irrigation  system;  it  is,  however,  distinct  from 
irrigation  operation. 

Cost  of  Pumping. — The  other  items  of  cost  are  operation, 
maintenance,  depreciation  and  interest.  Interest  in  any  case 
can  be  figured  from  the  amount  of  the  investment.  Operation 
cost  depends  on  the  size  of  the  plant  and  length  of  season.  The 
larger  irrigation  plants  have  not  been  in  use  sufficiently  long  to 
determine  the  average  cost  of  maintenance  or  depreciation.  The 
necessity  for  using  substantial  construction  and  a  good  grade  of 
equipment  has,  however,  been  demonstrated  if  such  costs  are  to 
be  kept  down  and  satisfactory  service  is  to  be  secured.  Little 
data  on  the  total  cost  of  pumping  has  been  made  available.  A 
number  of  plants  have  satisfactory  records  of  expenditures  but  do 
not  have  records  of  the  quantities  pumped  or  the  lift,  so  that 
unit  costs  cannot  be  secured.  The  cost  of  power  per  foot  acre- 
foot  can  usually  be  closely  approximated  where  electric  power  is 
used  as  the  general  efficiency  of  the  plant  may  be  known.  If  2 
kilowatt-hours  are  used  per  foot  acre-foot  the  cost  of  power,  if 
purchased,  will  usually  be  from  1.5  to  2.5  cents  per  foot  acre-foot 
for  plants  supplying  canal  systems.  The  cost  of  fixed  charges 
and  depreciation  are  more  variable.  The  acreage  cost  of  the 


GENERAL  OPERATION  235 

pumping  plant  alone  may  vary  from  $12  to  $25  or  more  per 
acre,  depending  on  the  area,  lift  and  character  of  the  plant. 

Depreciation  is  more  uncertain  in  amount.  The  labor  cost  of 
operation  is  also  variable.  In  1914  the  cost  of  pumping  on  the 
Minidoka  project,  a  three-lift  system  irrigating  about  40,000 
acres,  was  0.14  cents  per  foot  acre-foot  for  operation  and  0.30  cents 
for  depreciation.  Power  was  developed  by  the  project  under 
favorable  conditions  and  at  low  costs.  If  interest  and  general 
expense  are  included,  it  would  appear  that  water  for  irrigation 
should  be  pumped  by  plants  of  sufficient  size  to  be  economical 
at  a  cost  of  3.5  to  5  cents  per  foot  acre-foot  where  power  is  pur- 
chased. For  50-foot  lifts  this  would  equal  $1.75  to  $2.50  per 
acre-foot.  Where  the  power  can  be  generated  at  a  drop  or  by 
the  canal  system  the  cost  may  be  somewhat  less ;  where  the  opera- 
tion season  is  short  or  the  plant  poorly  designed  or  operated,  the 
unit  cost  may  exceed  these  figures. 

RELATIONS  OF  OPERATION  ORGANIZATION  AND  LAND  OWNERS 

Colonization. — Colonization  is  not  a  regular  part  of  the  duties 
of  an  irrigation  organization,  although  in  the  earlier  years  of  sys- 
tems developed  under  the  Carey  Act  or  by  private  capital  the 
operation  of  the  irrigation  system  is  under  the  control  of  those 
who  also  handle  the  colonization.  Distinct  personnel  may  be 
maintained  for  each  function  or  there  may  be  more  or  less  over- 
lapping of  duties.  On  smaller  systems  the  members  of  the  oper- 
ating force  may  be  called  on  to  aid  new  settlers  by  giving  advice 
regarding  the  preparation  of  land  and  methods  of  irrigation.  On 
larger  systems  a  separate  adviser  may  be  maintained. 

Close  cooperation  between  the  colonization  and  operation 
forces  is  necessary.  While  additional  settlers  are  still  being 
sought  it  is  usual  to  be  more  lenient  in  the  enforcement  of  rules 
with  those  already  on  the  ground.  The  preparation  of  land  plats 
and  checking  of  payments  for  water  can  be  handled  by  the  opera- 
tion force,  the  plats  being  made  and  kept  posted  by  the  engineer- 
ing department.  It  is  necessary  to  keep  in  close  touch  with  the 
land  selling  in  order  that  the  extension  of  laterals  and  construc- 
tion of  turnouts  may  be  made  as  needed. 

The  operation  organization  is  particularly  interested  in  one 
policy  of  colonization  which  is  coming  to  be  recognized  as  neces- 
sary. This  is  the  opening  of  the  project  in  definite  units  and  the 


236  IRRIGATION  SYSTEMS 

withholding  of  new  units  until  the  old  ones  are  nearly  sold  out. 
In  some  of  the  older  projects,  the  first  settlers  have  been  scattered 
over  large  areas  making  operation  difficult  and  expensive. 

Methods  of  land  colonization  are  improving.  It  is  now  real- 
ized that  more  than  a  purchase  contract  is  involved.  Where 
settlers  are  to  be  carried  for  future  payments,  those  who  are 
capable  of  success  or  have  capital  to  make  payments  are  the  only 
types  of  settlers  to  whom  a  company  can  afford  to  make  sales. 
The  difficulties  with  delinquent  payments,  the  bad  effect  on  other 
sales  of  those  who  fail  and  the  expense  of  securing  purchasers 
make  a  policy  of  care  in  the  selection  of  settlers  necessary.  Land 
speculators  are  undesirable  from  the  point  of  view  of  the  com- 
pany, as  their  lands  are  more  slowly  developed  and  their  owners 
more  easily  dissatisfied.  In  the  past  there  have  been  some  sys- 
tems where  the  first  purpose  of  colonization  has  been  the  securing 
of  sales  contracts  to  be  used  as  security  for  construction  work. 
This  condition  has  now  changed  as  settlers  cannot  be  secured 
for  large  systems  who  will  purchase  before  water  is  made  avail- 
able. Greater  expenditures  from  their  own  resources  are  now 
required  by  those  developing  irrigation  systems  for  land-coloniza- 
tion purposes  and  this  greater  investment  leads  to  a  more  per- 
manent interest  in  the  project  on  the  part  of  the  promoters. 

With  cooperative  companies  or  irrigation  districts  the  lands 
are  in  the  ownership  of  settlers  at  the  time  the  development  is 
made.  For  such  systems,  the  land  sales  are  individual  in  nature 
and  do  not  involve  the  operation  organization. 

The  rate  of  extension  of  the  irrigated  area  is  relatively  slow  in 
many  cases.  The  records  of  the  U.  S.  Reclamation  Service  show 
that  an  average  of  only  one-fourth  of  the  irrigable  area  is  irrigated 
in  the  second  year  of  operation  and  that  one-half  the  irrigable 
area  will  not  be  irrigated  before  from  4  to  6  years.  For  many 
systems  the  rate  of  development  has  been  slower  than  these 
amounts. 

Average  Size  of  Farm. — The  average  size  of  farm  units  is  a 
factor  both  in  colonization  and  in  the  operation  of  the  system. 
Larger  farms  mean  fewer  deliveries  and  less  detail  in  the  delivery 
methods.  If  the  average  size  of  farm  is  too  large,  large  capital 
or  an  excessive  length  of  time  are  required  for  its  complete  devel- 
opment. For  the  most  rapid  development  of  the  land  and  in- 
crease of  irrigated  area  small  farms  are  preferable.  Such  farms 
may  be  smaller,  when  developed,  than  sufficient  to  fully  occupy 


GENERAL  OPERATION  237 

or  support  the  farm  family.  The  limiting  of  the  farm  to  such  an 
area  that  the  capital  available  will  permit  of  its  rapid  develop- 
ment, followed  by  the  leasing  of  other  land  if  the  original  holding 
is  too  small,  is  to  the  interest  of  both  farmer  and  canal  company. 

The  desirability  of  having  fixed  sizes  of  farm  units  may  be 
questioned.  The  U.  S.  Reclamation  Service  has  discretionary 
powers  in  fixing  the  maximum  area  for  which  water-right  appli- 
cations will  be  received.  This  area  has  been  made  relatively 
small  in  some  cases.  The  proper  size  of  farm  unit  depends  as 
much  on  the  financial  resources  of  the  settler  as  on  any  other 
factor.  While  all  should  be  discouraged  from  taking  larger  areas 
than  can  be  developed  to  advantage,  fixing  too  low  a  maximum 
area  may  restrict  settlement  to  those  of  limited  capital.  The 
size  of  entry  can  be  fixed  only  in  the  case  of  land  within  govern- 
ment projects  and  such  limits  cannot  be  enforced  in  practice 
after  the  land  and  water  titles  are  in  private  ownership.  The 
economic  size  of  farm  varies  with  the  individual,  the  type  of 
agriculture  and  the  financial  resources  of  the  owner.  Like  other 
economic  questions  in  agriculture  it  must  be  worked  out  from  the 
point  of  view  of  the  farm.  In  irrigated  agriculture,  the  irrigation 
methods  must  be  adjusted  to  such  conditions  on  the  farm  rather 
than  to  attempt  to  adjust  conditions  on  the  farm  to  desired  irri- 
gation methods. 

Agricultural  Aid  to  Irrigators. — As  a  part  of  the  realization  of  the 
common  interest  of  irrigator  and  canal  operator,  or  of  the  new 
settler  and  the  colonization  of  irrigation  systems,  various  kinds  of 
agricultural  assistance  have  been  supplied  to  settlers  on  new 
systems. 

Demonstration  farms  have  been  used  in  some  cases.  The 
purpose  of  these  has  been  to  demonstrate  the  crop  possibilities 
of  the  locality,  mainly  for  use  in  land  sales.  It  is  now  recognized 
that  constructive  demonstration  work  requires  many  years  of 
experiment  under  consistent  direction  and  that  such  results  can 
best  be  secured  under  the  direction  of  either  the  State  agricultural 
colleges  or  the  U.  S.  Department  of  Agriculture.  While  demon- 
stration or  experiment  farms  are  now  in  operation  under  several 
systems  they  are  nearly  all  under  such  control.  Such  work  is 
properly  handled  by  State  or  federal  funds  as  the  results  are  of 
general  public  benefit.  It  is  also  now  recognized  that  the  results 
on  raw  lands  are  not  necessarily  indicative  of  future  results  after 
soils  have  been  in  use. 


238  IRRIGATION  SYSTEMS 

More  effective  aid  can  be  given  to  new  settlers  directly  on  their 
own  farms.  Some  large  companies  have  employed  agricultur- 
ists for  such  work,  who  correspond  to  the  county  agents  or  farm 
advisors  now  employed  to  some  extent  by  the  government  and 
counties.  Such  men  can  be  of  much  assistance  in  preventing 
mistakes  by  those  new  to  the  locality  or  in  improving  practice  for 
older  communities.  From  the  direct  point  of  view  of  the  opera- 
tion of  the  canal  system,  the  advice  given  on  preparing  land  for 
irrigation  is  the  most  important.  The  single  factor  which  affects 
the  duty  of  water  to  the  largest  extent  is  the  care  used  in  prepar- 
ing the  land.  For  permanent  crops  the  character  of  the  prepara- 
tion of  the  land  largely  controls  the  duty  of  water  and  size  of 
irrigation  head  for  several  years.  If  settlers  can  be  given  advice 
on  the  methods  suited  to  their  lands  and  be  induced  to  plan  their 
ditches  and  lands  so  that  the  most  economical  size  of  irrigation 
head  can  be  used,  the  problems  of  delivery  of  water  both  in  method 
and  amount  will  be  much  simplified.  Such  advisors  can  also 
be  of  much  assistance  in  aiding  the  settler  to  choose  the  crops  to 
be  grown  and  crop  methods,  in  purchasing  stock  and  in  selling  his 
products. 

The  regular  operation  force  may  to  some  extent  assist  in  such 
work.  This  can  be  done  through  general  advice  and  cooperation. 
On  some  systems,  instrumentmen  employed  by  the  company  are 
used  to  survey  the  land,  make  topographic  maps  and  plan  and 
stake  out  the  farm  system.  On  others,  aid  is  given  only  to  the  ex- 
tent of  laying  out  ditch  grades.  -This  may  be  to  the  interest  of 
the  canal  system  as  the  farm  takeouts  can  be  planned  in  connec- 
tion with  the  sub-lateral  system  and  arrangements  made  for 
using  uniform  sizes  of  irrigating  heads  where  other  conditions 
permit. 

Ownership  of  Land  by  Operation  Force. — The  ownership  of 
lands  under  a  canal  system  by  members  of  the  operation  organi- 
zation is  a  question  which  has  given  trouble  on  some  systems. 
This  is  particularly  true  of  government  systems;  for  other  forms 
of  organization  the  outside  activities  of  employees  are  not  so 
closely  restricted.  Any  such  ownership  should  be  for  actual  use 
and  not  for  speculation.  The  arguments  in  favor  of  such  owner- 
ship are  that  the  experience  will  give  those  in  charge  a  better 
understanding  of  the  difficulties  of  the  land  owners,  tend  to  make 
changes  in  the  management  and  other  officials  less  frequent  and 
create  a  better  spirit  between  the  operation  force  and  the  users. 


GENERAL  OPERATION  239 

The  arguments  against  it  are  that  the  operation  force  may  favor 
the  vicinity  in  which  they  own  land  in  time  of  water  shortage  and 
that  they  may  give  time  and  attention  to  their  farms  which  should 
be  given  to  the  canal  system.  There  does  not  seem  to  be  any 
marked  advantage  to  either  argument;  if  officials  desire  and  have 
the  means  to  own  farms  under  the  system,  they  should  be  per- 
mitted to  do  so,  but  such  ownership  is  not  essential. 

It  may  be  found  desirable  to  provide  ditch  riders  with  houses 
and  small  areas  of  land.  This  is  done  as  a  part  of  the  compensa- 
tion and  as  an  encouragement  to  permanence  in  employment  and 
is  separate  from  the  question  of  ownership  of  land  for  general 
agricultural  purposes. 

Restricting  Use  of  Water. — The  extent  to  which  the  operation 
force  can  go  in  restricting  excessive  use  of  water  is  difficult  to  de- 
termine. Where  the  excess  use  is  practised  by  only  a  few  or 
comes  within  the  scope  of  the  rules  governing  waste,  the  cases  can 
be  handled  individually.  Where  the  practice  is  that  of  using 
more  water  than  is  required,  although  surface  waste  may  not  be 
evident,  control  is  more  difficult.  Generally,  the  management 
cannot  go  beyond  the  point  to  which  public  opinion  will  support 
interference  with  the  individual.  Such  public  opinion  will 
usually  support  restrictive  measures  against  users  where  waste 
is  noticeable  or  to  the  injury  of  others,  either  from  actual  waste  or 
due  to  the  resulting  reduction  in  their  supply.  Where  the  water 
supply  is  ample  in  amount,  little  support  can  be  secured  for  a 
policy  which  restricts  use  unless  the  direct  injury  is  apparent. 
While  the  operation  force  may  be  the  actual  leaders  and  organizers 
of  public  opinion,  their  actions  in  restricting  use  should  appear  to 
come  from  an  outside  demand  by  the  users,  rather  than  on  their 
own  initiative.  To  attempt  to  force  a  control  of  the  use  of  water 
by  the  operation  organization  engenders  a  direct  opposition  to 
such  control  which  only  increases  the  time  before  a  more  careful 
use  can  be  secured.  The  duties  of  the  strictly  operation  force  are 
administrative;  it  is  not  desirable  that  they  be  also  judicial  in  re- 
gard to  policy  except  in  so  far  as  they  may  be  in  accord  with  the 
users  or  compelled  by  necessity.  The  efforts  of  operation  em- 
ployees should  be  educational  in  nature,  calling  attention  to  the 
results  secured  by  those  practising  economy  in  the  use  of  water, 
keeping  records  by  which  the  identity  of  the  "  water  hog"  becomes 
known  and  advocating  diversified  crops  or  crops  of  lower  water 
requirement  where  practical* 


240  IRRIGATION  SYSTEMS 

The  quantity  of  water  to  which  a  farm  is  entitled  is  determined 
by  the  terms  of  some  agreement,  such  as  a  water-right  contract,  or 
by  the  number  of  shares  held  in  cooperative  companies,  that  is, 
the  user  is  protected  in  his  water  supply  up  to  some  total  rate  of 
use  or  total  quantity.  Within  the  limits  of  such  rights,  the  user 
is  generally  the  judge  of  his  needs  and  restrictive  control  is  more 
largely  a  matter  of  diplomacy  than  of  right. 

The  size  of  irrigation  head  which  is  used  on  each  farm  affects 
both  the  farmer  and  the  delivery  methods  of  the  system.  The 
interests  of  both  are  to  have  as  large  heads  used  as  can  be  handled 
effectively  without  waste.  The  actual  size  of  head  used  depends 
on  many  factors  and  varies  widely.  On  many  systems  the  earlier 
practice  has  developed  the  use  of  smaller  heads  than  those  which 
give  the  greatest  efficiency.  The  change  to  larger  heads  can  only 
take  place  gradually  as  the  enlarging  of  farm  ditches  and 
structures  is  required.  To  attempt  to  force  the  use  of  larger 
irrigation  heads  before  such  changes  in  farm  systems  have  been 
made  will  result  in  direct  opposition  which  will  usually  delay  the 
actual  changes  beyond  the  time  when  their  adoption  might  have 
been  secured  had  no  attempt  to  force  the  change  been  made. 

Determination  of  Operation  Policy. — For  about  75  per  cent, 
of  the  area  irrigated,  the  owners  of  the  land  control  the  canal  sys- 
tem. For  one-half  of  the  remaining  area  the  control  of  the  sys- 
tem will  eventually  be  turned  over  to  the  land  owners.  On  such 
systems  the  policies  are  determined  by  the  land  owners  through 
their  elected  officers,  the  duties  of  those  directly  concerned  with 
the  operation  being  to  carry  such  policies  into  effect.  The  re- 
sponsibility for  the  policies  themselves  rests  with  those  having 
the  power  over  their  adoption.  This  does  not  mean  that  the 
operation  officials  should  not  use  their  influence  in  advising  regard- 
ing the  policy  to  be  followed,  but  the  responsibility  for  the  choice 
belongs  with  those  having  the  power  to  make  it.  Where  the 
users  and  management  are  in  proper  accord  the  recommendations 
of  the  management  will  usually  be  followed. 

On  systems  not  owned  or  controlled  by  the  users,  policies  can 
be  adopted  by  the  owners  which  may  not  be  desired  by  the  users 
and  the  operation  force  may  be  able  to  handle  the  system  in 
ways  opposed  by  the  users.  Such  practices  will  not  be  per- 
manently successful,  however.  The  majority  of  the  systems 
which  are  not  owned  by  the  users  are  subject  to  the  control  of 
public  service  commissions  both  as  to  rates  and  character  of 


GENERAL  OPERATION  241 

service.  The  general  character  of  service  and  maximum  rates 
on  Carey  Act  systems  until  they  pass  into  the  control  of  the  users 
are  covered  in  the  contract  between  the  State  and  the  construct- 
ing company.  Even  if  the  users  do  not  actually  control  the  sys- 
tem they  are  able  to  exert  a  very  strong  influence  on  the  opera- 
tion policies,  as  no  system  can  succeed  against  the  opposition  of 
the  land  owners. 

Irrigation  may  be  and  is  an  absolute  necessity  for  crop  produc- 
tion in  many  localities.  Given  a  water  supply,  however,  its  use 
becomes  only  one  of  several  factors  involved  in  the  success  of 
the  settlers.  The  desire  of  the  farmer  is  to  produce  crops  most 
profitably,  that  of  the  canal  system  to  have  the  most  economical 
use  made  of  the  water  in  order  to  reduce  the  expense  of  operation. 
These  two  objects,  particularly  on  new  projects,  do  not  coincide 
in  many  cases.  In  case  of  conflict  the  farmer's  point  of  view 
will  generally  dominate  if  the  system  is  to  succeed. 

REFERENCES  FOR  CHAPTER  VIII 

GRIFFIN,  J.  M. — Adjustment  of  Complaints  of  Water  Users,  1911,  First 

Conference  of  Operating  Engineers,  Boise,  Idaho. 
BARKER,  D. — Regulations  and  Methods  to  be  Adopted  to  Care  for  Waste 

Water  from  Farms  Adjacent  to  Canals,  1914,  Third  Annual  Conference 

of  Operating  Engineers,  Boise,  Idaho. 
COTTON,  W.  O. — Running  Winter  Water  in  Canals  for  Stock  and  Domestic 

Purposes,    1913,   Second   Conference  of  Operating  Engineers,    Boise, 

Idaho. 
KAYS,  M.  R. — Winter  Stock  Water:  Methods  of  Running  and  Effect  on 

Canal  System  and  Raise  of  Ground  Water,  1914,  Third  Annual  Con- 
ference of  Operating  Engineers,  Boise,  Idaho. 

O'DONNELL,  I.  D. — Winter  Water  for  Stock  and  Domestic  Uses,  Reclama- 
tion Record,  December,  1915. 
Snake  River  Distribution,  Reports  of  Idaho  State  Engineer,  1911-12  and 

1913-14. 

Reports  Colorado  State  Engineer,  1909-10. 
TALLMAN,    A.   V. — Canal   Deliveries  from  the   Boise   River,    1916,    Fifth 

Conference  of  Operating  Engineers,  Boise,  Idaho. 
WILCOX,  E.  A. — Hydro-Electric  Developments  and  Enterprises  in  Southern 

Idaho  and  Their  Application  to  Irrigation  Pumping  Projects,  Journal 

Idaho  Society  of  Engineers,  June,  1913. 
BERG,  E.  V. — Pumping  for  Irrigation,  Journal  Idaho  Society  of  Engineers, 

June,  1913. 
DIBBLE,  B. — Cost  of  Pumping  for  Irrigation,  Journal  Electricity,  Power 

and  Gas,  Feb.  27,  1915. 

Data  in  15th  Annual  Report  of  U.  S.  Reclamation  Service. 
16 


242  IRRIGATION  SYSTEMS 

HARLAN,   G.  E. — Method  of  Taking  Crop  Census  and  Its  Value,   1914 

Third  Conference  of  Operating  Engineers,  Boise,  Idaho. 
Ownership  of  Land  by  Employees,   Discussion  and  Committee  Report, 

1913,  Conference  of  Operating  Engineers,  Great  Falls,  Mont. 
RIGG,  E.  L. — Ownership  of  Land  by  Men  in  Responsible  Charge,  1914,  Third 

Conference  of  Operating  Engineers,  Boise,  Idaho. 
DARLINGTON,  E.  B. — Economic  Size  of  an  Irrigation  Farm,  1915,  Fourth 

Conference  of  Operating  Engineers,  Boise,  Idaho. 
Small  versus  Large  Farm  Units,  Reclamation  Record,  June,  1914. 
HARDING,  S.  T. — Rate  of  Development  of  Irrigation  Projects,  Journal  of 

Electricity,  Power  and  Gas,  July  15,  1916. 
TEELE,  R.  P. — Slow  Rate  of  Utilization  of  Irrigation  Works,  Engineering 

News,  Aug.  3,  1916. 


CHAPTER  IX 
OPERATION  AND  MAINTENANCE  ACCOUNTS 

While  the  advantages  of  keeping  the  accounts  of  different 
irrigation  companies  by  some  uniform  system  have  frequently 
been  pointed  out,  yet  there  has  been  little  general  progress  toward 
such  uniformity  although  there  has  been  a  general  improvement 
in  the  character  of  the  accounting  systems  used.  Several  of  the 
Western  States  now  have  public  utility  commissions  whose  juris- 
diction extends  to  the  accounts  of  the  utilities  in  these  States. 
The  number  of  irrigation  companies  which  are  classed  as  public 
utilities  is  relatively  small,  however,  and  the  system  and  sub- 
division of  accounts  which  have  been  prescribed  for  such  com- 
panies are  those  required  for  all  water  companies  and  were 
planned  mainly  for  municipal  water  systems.  The  systems  of 
prescribed  accounts  are  quite  similar  in  the  different  States  and 
furnish  a  satisfactory  statement  of  the  financial  condition  of  the 
companies.  They  do  not,  however,  give  sufficient  detail  to  fur- 
nish all  the  costs  which  it  is  desirable  for  those  responsible  for  the 
management  of  an  irrigation  company  to  have  and  further  sub- 
division should  be  used.  For  utilities  particular  emphasis  is 
placed  on  the  accounts  showing  the  capital  investments  and  con- 
ditions; for  the  non-profit-earning  irrigation  companies,  such  as 
irrigation  districts  and  cooperative  companies,  these  investment 
accounts  are  of  relatively  less  importance  than  the  direct  opera- 
tion and  maintenance  accounts.  Uniform  accounting  methods 
are  used  on  the  projects  of  the  U.  S.  Reclamation  Service.  These 
are  carried  to  more  detail  than  is  usual  with  other  forms  of 
organization. 

The  forms  of  irrigation  organizations  owned  and  controlled  by 
the  owners  of  the  lands  served  comprise  much  the  greatest  pro- 
portion of  irrigation  companies.  These  vary  so  widely  in  organi- 
zation, size  and  conditions  of  operation  that  it  would  be  difficult 
to  plan  a  system  of  accounts  suited  to  all  systems.  A  general 
classification  with  the  detail  to  which  it  is  carried  varying  with  the 
size  of  the  system  or  other  factors  represents  as  great  uniformity 

243 


244  IRRIGATION  SYSTEMS 

as  seems  warranted.  This  is  recognized  in  the  prescribed  ac- 
counts for  utilities  where  three  classes  of  systems  are  used  based 
on  the  amount  of  the  operating  revenues.  These  are  usually 
given  as  Class  A  corporations  for  those  having  average  annual 
operating  revenues  exceeding  $100,000;  Class  B,  for  those  be- 
tween $100,000  and  $25,000,  and  Class  C  for  those  less  than 
$25,000. 

The  purpose  of  any  system  of  accounts  is  to  supply  the  costs  of 
various  operations  and  the  resulting  financial  condition  of  the 
enterprise.  The  keeping  of  accounts  is  a  matter  of  accounting; 
the  following  discussion  has  reference  to  the  kinds  of  records 
needed  for  irrigation  systems  and  not  the  technical  questions  of 
actual  accounting  itself.  Besides  the  strictly  operation  and 
maintenance  accounts  any  system  will,  of  course,  have  to  carry 
individual  ledger  accounts  with  all  parties  to  whom  payments  are 
made  or  from  whom  revenues  are  received.  It  is  the  classification 
of  the  items  of  expense  to  show  operation  and  maintenance  costs 
which  forms  the  basis  of  general  accounting  systems  for  irrigation 
companies. 

GENERAL  CLASSES  OF  ACCOUNTS 

Accounts  can  be  divided  into  certain  general  classes.  Those 
recognized  in  the  prescribed  system  of  the  California  Railroad 
Commission  are  the  general  asset  and  liability  and  balance-sheet 
accounts;  fixed  and  tangible  capital;  income  accounts;  surplus 
and  deficit  accounts;  operating  revenues;  pumping,  distribution, 
commercial  and  general  expenses;  taxes;  amortization  of  capital; 
and  clearing  accounts.  Of  these  general  accounts,  operating 
expenses,  amortization  of  capital  or  depreciation  and  clear- 
*ing  accounts  most  directly  concern  irrigation  operation  and 
maintenance. 

The  division  between  operation  and  maintenance  is  not  made  in 
many  systems.  Such  a  division  is  essential  if  the  costs  of  differ- 
ent years  are  to  be  comparable.  For  given  conditions  operation 
costs  may  be  fairly  uniform  from  year  to  year,  maintenance  may 
fluctuate  materially.  Where  the  same  employees  are  used  for 
both  operation  and  maintenance  the  distinction  may  be  more  or 
less  arbitrary  and  the  difficulty  of  making  it  has  prevented  many 
companies  from  separating  these  items. 

The  distinction  between  routine  operation,  maintenance  or 
repairs,  replacements,  and  betterments  are  often  difficult  to  make 


OPERATION  AND  MAINTENANCE  ACCOUNT      245 

in  actual  practice.  The  public  utility  commissions  of  Idaho, 
Washington  and  Arizona  use  the  following  definition  with  only 
slight  differences  in  wording: 

"Maintenance  should  be  understood  to  mean  'upkeep'  and  should 
cover  all  expenditures  for  current  or  ordinary  repairs,  renewals  or  re- 
placements of  property  resulting  through  wear  and  tear,  or  through 
those  casualties  which  are  incidental  to  the  nature  of  the  operation 
and  which  expenditures  are  necessary  in  order  to  keep  up  the  pro- 
ductive capacity  of  the  plant  to  its  original  or  equivalent  state  of 
efficiency.  When,  however,  a  complete  replacement  of  any  building 
or  structure,  facility  or  unit  of  equipment  is  made  necessary  regardless 
of  such  current  expenditures,  the  uncurrent  or  extraordinary  repairs, 
renewals  or  replacements  made  necessary  will  be  charged  to  the 
Depreciation  Reserve,  accumulated  for  that  purpose." 

The  classification  used  by  the  Pacific  Gas  and  Electric  Co.  is 
defined  as  follows: 

"The  charges  which  are  made  to  capital  under  the  general  head  of 
Maintenance  of  Capital,  are  generally  termed  repairs,  and  are  thereby 
more  specifically  designated  as  expenditures,  necessary  to  keep  the 
facilities,  structures  or  units  of  equipment  up  to  the  standard  of  operat- 
ing efficiency.  When  through  wear  and  tear  or  through  casualty  it 
becomes  necessary  to  replace  or  repair  some  part  of  any  structure, 
facility  or  unit  of  equipment,  and  the  extent  of  such  repairs  does  not 
amount  to  a  substantial  change  of  identity  in  such  structures,  facility 
or  unit  of  equipment,  such  work  is  to  be  treated  as  a  repair  and  charged 
to  the  subaccounts  under  maintenance.  Replacements  include  all 
substitutions  for  existing  structures,  facilities  or  units  of  equipment, 
which  have  been  exhausted,  or  become  inadequate  in  service,  and 
when  the  replacement  of  such  structures,  facilities  or  units  of  equipment 
must  be  considered  a  replacement,  and  not  charged  to  any  of  the  sub- 
accounts  under  maintenance,  but  to  Accrued  Amortization  of  Capital 
— a  general  account.  When  a  substitution,  for  existing  structures, 
facilities  or  units  of  equipment,  has  a  substantially  greater  capacity 
than  that  structure,  facility  or  unit  of  equipment  for  which  it  is  sub- 
stituted, the  value  of  the  original  structure,  facility  or  unit  of  equip- 
ment, less  the  salvage  of  old  material,  as  junk  or  stock  shall  be  charged 
as  a  replacement  and  credited  to  capital.  The  cost  of  the  substituting 
structures,  facilities  or  units  of  equipment,  shall  constitute  an  addition 
and  betterment  to  capital  and  be  charged  to  appropriate  subaccount  in 
additions  and  betterments  of  capital — a  division  account." 

The  Oregon  Railroad  Commission  gives  more  detailed  classi- 
fications as  follows: 


246  IRRIGATION  SYSTEMS 

"  Ordinary  repairs  include  replacements  of  minor  or  short-lived  parts 
of  structures,  equipment,  or  facilities;  replacement  of  minor  parts  of 
structures  or  equipment  made  necessary  by  reason  of  faulty  construc- 
tion, excessive  strains,  mechanical  injuries,  or  other  minor  casualties 
not  provided  against  in  charge  for  depreciation  of  plant  and  equip- 
ment; rearrangements  and  changes  in  location  of  equipment,  etc. 
Ordinary  repairs  are  not  required  to  be  taken  into  account  in  fixing  a 
rate  of  depreciation.  Extraordinary  repairs  include  restoring  to  an 
efficient  or  proper  condition  buildings,  structures,  or  other  units  of 
property  which  have  deteriorated;  substituting,  in  order  to  maintain 
normal  efficiency,  new  parts  for  old  parts  of  continuous  structures, 
where  such  substitutions  do  not  amount  to  a  practical  replacement  of 
any  considerable  length  of  such  continuous  structures;  restoring  the 
condition  of  property  damaged  by  flood,  fire  or  other  casualties;  recover- 
ing salvage  and  removing  retired  or  abandoned  property  in  connec- 
tion with  the  above  kinds  of  work.  Extraordinary  repairs  should  be 
provided  for  by  adequate  charges  to  depreciation.  When  it  is  neces- 
sary substantially  to  reconstruct  or  to  replace  a  major  portion  of  any 
unit  of  property  or  any  important  section  of  a  continuous  structure,  the 
cost  should  be  handled  through  the  Capital  account;  that  is,  the  cost 
of  property  removed  or  replaced  should  be  credited  to  the  appropriate 
Fixed  Capital  accounts,  and  the  new  property  should  be  charged 
thereto." 

Such  routine  repairs  as  removal  of  vegetation,  or  control  of 
burrowing  animals  which  may  be  handled  by  the  operation  force 
can  be  charged  to  operation,  particularly  where  the  work  done  is 
effective  for  less  than  one  season  or  is  carried  on  continuously 
throughout  each  season.  When  the  repairs  are  those  covered  by 
the  usual  annual  canal  cleaning,  or  minor  changes  in  structures 
which  would  be  classed  as  ordinary  upkeep,  they  should  be 
charged  as  maintenance.  When  the  repairs  are  of  more  impor- 
tant nature  such  as  those  which  would  only  be  made  in  occasional 
years  or  when  they  constitute  either  an  entire  replacement  or  a 
substantial  renewal  of  part  of  a  structure  they  should  be  handled 
through  depreciation  accounts.  Where  replacement  consists  of 
the  substitution  of  a  structure  of  better  type  or  larger  capacity  the 
additional  cost  over  that  of  duplication  of  the  original  structure 
becomes  a  betterment.  These  methods  are  based  mainly  on  the 
required  accounts  for  public  utility  companies  where  the  rates 
charged  cover  interest  on  the  value  and  depreciation  as  well  as 
operation  and  maintenance.  For  such  companies  it  is  necessary 
to  carry  book  accounts  for  the  value  of  the  system  in  use.  With 


OPERATION  AND  MAINTENANCE  ACCOUNT      247 

non-dividend  or  non-interest-earning  forms  of  organization,  which 
include  the  greater  number  of  irrigation  systems,  such  book  ac- 
counts of  value  are  seldom  maintained.  Instead  of  carrying  a 
reserve  account  for  depreciation  both  replacements  and  better- 
ments are  met  as  they  arise.  With  mutual  or  stock  companies 
the  assessments  are  made  to  cover  the  annual  expenses  which 
may  vary  widely  depending  on  the  amount  of  replacement  or 
betterment  work  done.  The  individual  stockholders  finance  their 
own  assessments  in  such  cases.  Where  the  betterments  are  ex- 
tensive, notes  or  bonds  may  be  issued  by  the  company  to  distribute 
the  expense  over  a  series  of  years.  Irrigation  districts  handle 
their  accounts  similarly,  the  use  of  bonds  for  larger  improvements 
being  more  general.  The  annual  assets  and  liabilities  statements 
of  some  irrigation  districts  give  the  original  cost  or  money  ex- 
pended from  bond  funds  plus  inventory  accounts  on  hand  as  the 
total  assets  without  attempting  to  give  figures  on  present  value 
of  the  system.  For  such  forms  of  organization  this  method  is 
satisfactory,  as  assessments  are  based  on  expenditures  and  not 
on  legal  earnings.  Many  such  companies  carry  a  construction 
fund  and  a  repair  fund,  which  correspond  in  a  general  way  with 
betterments  or  additions  to  capital  and  maintenance  respec- 
tively, although  there  may  be  a  good  deal  of  difference  in  the 
practice  in  the  charges  for  replacements.  Where  extraordinary 
repairs  are  paid  for  by  loans,  secured  at  the  time  of  repair  and 
paid  during  ensuing  years,  the  process  is  the  reverse  of  that  used 
in  accumulating  a  depreciation  reserve  over  a  series  of  years 
prior  to  making  the  extraordinary  repair.  In  irrigation  depre- 
ciation is  principally  that  of  structures.  With  proper  annual 
maintenance,  earth  canals  will  improve  rather  than  deteriorate, 
and  depreciation  accounts  will  not  usually  be  required.  The 
actual  rate  of  depreciation  and  useful  life  of  structures  depends 
upon  the  materials  used  and  conditions  of  service  which  have 
been  discussed  in  Chapter  II. 

ACTUAL  ACCOUNTS 

Owing  to '  the  wide  variation  in  conditions  on  different 
irrigation  systems  certain  functional  subdivisions  are  neces- 
sary if  the  operation  and  maintenance  costs  are  to  be  at  all 
comparable. 

The  total  annual  costs  per  acre  of  a  system  having  a  long  diver- 


248  IRRIGATION  SYSTEMS 

sion  canal  is  not  fairly  comparable  with  one  situated  more  favor- 
ably even  if  the  conditions  of  actual  use  of  water  are  similar.  In 
the  same  way  storage  or  pumping  costs  should  be  separated. 
The  larger  or  functional  divisions  used  by  the  U.  S.  Reclamation 
Service  are  those  of  (1)  development,  (2)  carriage,  (3)  distribu- 
tion, and  (4)  drainage  and  flood  protection.  In  addition  such 
accounts  as  general  expenses  and  depreciation  reserves  may  be 
separately  kept  or  distributed  to  these  functional  divisions. 
Some  companies  distinguish  only  collection  or  development  ex- 
penses and  distribution  expenses  which  would  include  carriage 
and  distribution.  With  some  forms  of  organization  drainage 
and  flood  protection  of  the  irrigated  land  are  not  handled  by  the 
irrigation  system  but  by  separate  organizations.  The  general 
operation  accounts  specified  by  the  utility  commissions  for  water 
companies  are  usually  (1)  pumping,  (2)  distribution,  (3)  com- 
mercial, and  (4)  general  and  miscellaneous  expenses,  (5)  taxes, 
and  (6)  depreciation.  These  are  better  suited  to  municipal 
water-supply  systems  than  to  irrigation. 

For  systems  sufficiently  large  to  have  definite  operation  organi- 
zations it  should  be  desirable  to  recognize  development,  carriage 
to  the  irrigated  area  and  distribution.  Development  would  in- 
clude the  cost  of  storage  including  canals  for  filling  if  such  canals 
are  used  or  of  pumping  from  wells.  On  many  systems  diverting 
directly  from  the  streams  such  accounts  would  not  be  used. 
Carriage  should  cover  the  cost  of  conveyance  to  the  boundaries 
of  the  area  of  use  which  may  be  either  by  means  of  a  diversion 
canal  or  by  a  pumping  lift  from  the  stream.  This  division  may 
be  neglected  on  smaller  systems  covering  relatively  low-lying 
lands;  it  is  important  on  systems  having  relatively  long  main 
canals.  Distribution  should  cover  the  costs  within  the  area 
served  which  will  be  more  nearly  comparable  on  an  acreage  basis. 
Judgment  is  of  course  essential  in  the  selection  of  these  divisions. 
Some  lands  may  be  served  from  the  diversion  canal,  making  the 
division  between  carriage  and  distribution  more  or  less  indefinite. 
Where  water  is  delivered  to  laterals  only  or  wholesaled,  carriage 
and  distribution  may  be  combined.  Where  the  storage  is  of  a 
regulatory  nature  rather  than  for  the  actual  water  supply  it  may 
be  classed  either  with  development  or  carriage. 

It  will  also  be  desirable  to  carry  accounts  for  general  office  ex- 
penses which  can  be  distributed  or  not,  more  usually  not,  to  the 
four  general  divisions.  Accounts  of  other  business  may  be  car- 


OPERATION  AND  MAINTENANCE  ACCOUNT      249 

ried  in  the  same  accounting  office  depending  on  the  nature  of  the 
organization.  Where  the  irrigation  company  carries  on  power, 
land  sales,  or  municipal  supply  such  operations  should  be  treated 
separately  in  the  accounts  and  in  some  cases  separate  incorpora- 
tions will  be  made  for  their  conduct. 

The  distinction  between  supplies  and  materials  used  in  repairs 
may  also  be  made  in  the  maintenance  accounts.  Supplies  are 
used  in  the  construction  but  do  not  become  a  part  of  the  finished 
structures,  whereas  materials  do.  Also,  equipment  such  as  hand 
tools  are  generally  classed  as  supplies  if  their  probable  life  is  less 
than  1  year.  Equipment  subject  to  transfer  from  .one  division 
of  the  work  to  another  may  be  carried  in  a  general  equipment 
account  and  the  depreciation  for  actual  use  charged  to  the  work 
on  which  it  is  used. 

Within  each  of  these  general  divisions  of  accounts  the  sub- 
accounts  should  be  chosen  to  give  the  costs  of  similar  items  under 
the  same  accounts.  Maintenance  and  operation  should  be  sub- 
divided. In  maintenance  it  is  desirable  to  group  structures  of 
similar  length  of  life  particularly  if  regular  depreciation  accounts 
are  being  used.  This  would  give  subaccounts  for  maintenance 
of  wooden  structures,  concrete  structures,  tunnels,  steel  pipe, 
lined  canal,  earth  canals  and  possibly  further  detail  on  some 
systems. 

Separate  maintenance  costs  may  be  kept  for  special  large 
structures.  A  large  flume  on  a  system  may  represent  a  large 
part  of  the  cost  of  the  system  so  that  it  is  desirable  to  segre- 
gate its  maintenance  costs.  These  will  then  be  of  much  aid 
in  judging  of  the  economy  of  the  type  of  structure  used  when 
its  replacement  is  necessary.  Also,  the  accounts  for  parti- 
cular types  of  structures  such  as  measuring  devices,  certain 
kinds  of  drops  or  delivery  gates  may  be  segregated  if  of  suffi- 
cient importance. 

A  suggested  general  outline  showing  some  of  the  subaccounts 
recognized  by  various  systems  is  given  in  the  following  tabula- 
tion. With  many  companies  all  divisions  would  not  be  required. 
With  small  companies  less  detail  may  be  needed.  Where  the 
expenditures  under  any  division  are  large  further  detail  may  be 
useful.  For  special  reasons  the  costs  of  particular  items  such  as 
cost  of  silt  removal  by  different  methods,  or  maintenance  of 
canals  under  different  systems  of  handling  may  be  kept. 


250  IRRIGATION  SYSTEMS 

Outline  Schedule  of  Accounts 
DEVELOPMENT. 
Reservoirs. 

Operation. — Gate  tenders,  watchmen,  labor,  supplies. 

Maintenance. — Repairs  to  dams,  inlet  and  outlet  structures, 

labor,  materials  and  supplies. 
Diversions  to  Storage. — Detail  as  for  reservoirs. 
Diversions  from  Storage. — Detail  as  for  reservoirs. 
Pumping  Plants. 

Operation. — Supervision    if    directly    chargeable,    labor    of 

attendance,   supplies,   purchase  of  power  or  detail   cost  of 

generation. 

Maintenance  of  pumping  equipment  and  buildings. 
Drainage  and  Flood  Protection. — To  development  system  only. 

Administration  of  Water  Rights.     Costs  of  water  commis- 
sioners, stream  patrol,  etc.,  charged  to  general  expenses  in 

some  systems. 

Purchase  of  water,  such  as  storage  from  other  systems. 
CARRIAGE. 

Operation. — Supervision,  gate  tenders,  labor  and  supplies  on 

diversion,   patrolmen   on   canals,   labor   and   supplies,   other 

operating  labor  and  supplies,  such  as  controlling  vegetation  or 

burrowing  animals. 

Maintenance. — Labor,  material  and  supplies  for  repairs  to 

diversion  dam  and  headworks,  canal  breaks,  cleaning  canals, 

repairs  to  concrete,  wood  and  metallic  structures. 

General. — Damages  from  breaks  and  injuries,  roads,  lands, 

buildings,  distribution  of  clearing  accounts. 
DISTRIBUTION. 

Operation. — Superintendence,    ditch   riders,    other   operation 

labor  exclusive  of  maintenance. 

Maintenance. — Labor,  material  and  supplies,  repairing  canal 

breaks,  cleaning  earth  canals,  repairs  to  concrete,  wood  and 

metallic  structures. 

General. — Damages  from  breaks  and  injuries,  roads,  lands, 

buildings,  distribution  of  clearing  accounts. 
GENERAL. 

Salaries  and  Expenses. — General  officers  having  supervision 

of    all    work,    clerical    employees,    engineering    department, 

general  charges,  hydrographic  work,  directors'  expense. 

Supplies. — Stationery,  postage,  printing. 

Telephone. — Operation  and  maintenance  labor,  material  and 

supplies. 

Buildings. — Light  and  heat,  rent,  repairs. 


OPERATION  AND  MAINTENANCE  ACCOUNT      251 

Taxes. 

Insurance. 

Interest. 

Equipment. — Furniture,  engineering  instruments,  etc. 

Legal  Expenses. — General  costs,  legal  retainers,  etc.     Damages 

charged  directly  to  the  division  affected. 

Undistributed  adjustments  to  balance  annual  and  general 

inventories. 

CLEARING  ACCOUNTS. 

Storehouse. — Labor,  supplies,  rent,  fuel,  light. 
Camp  Maintenance. — Labor,  fuel,  light  and  rent  maintaining, 
moving,  repairs,  water  supply,  supplies. 

Messes. — Labor   cooks   and   assistants,   food,   supplies,   fuel, 
light,  rent,  moving  mess,  repairs  to  equipment. 
Corrals. — Labor,  light  and  rent  maintaining,  feed,  hay  and 
grain,  shoeing,  veterinary,  repairs  to  wagons,  etc.,  moving, 
supplies. 

Shop  Expense. — Labor  shop  employees,  materials  used,  sup- 
plies for  shop,  rent,  fuel,  light,  miscellaneous. 
Automobile  and  Motorcycle. — Labor,  gasoline,  lubricating  oil, 
other  supplies,  tire  renewals  and  repairs,  other  repairs. 
Equipment. — Inventory  and  transfer  account  including  re- 
pairs and  depreciation  of  equipment  subject  to  transfer  from 
one  division  to  another. 

DRAINAGE  AND  FLOOD  PROTECTION  OF  IRRIGATED  LANDS. 

Operation  and  maintenance  in  detail  dependent  on  extent  used. 

RESERVES. 

Depreciation  when  used. 
Funds  for  bond  retirement. 

SEPARATE  OPERATIONS. 

Commercial  power,  land  sales,  water-right  sales,  domestic  use, 
handled  as  separate  undertakings. 

In  the  segregation  of  charges  to  items  or  accounts  it  is  usual  to 
employ  some  form  of  account  number  or  key  system.  This  may 
be  done  by  giving  a  letter  or  number  to  each  of  the  general  or 
functional  divisions,  a  similar  letter1  or  number  to  each  feature 
under  the  functional  division,  and  numbers  to  the  individual  ac- 
counts under  each  feature.  This  facilitates  both  field  and  office 
classification  and  is  now  in  general  use  on  government,  railroad 
and  other  large  work.  Key  books  or  sheets  of  account  numbers 
are  furnished  to  those  making  the  segregations. 

The  extent  to  which  costs  such  as  construction  work  on  the 
larger  replacements  should  be  kept  in  detail  in  the  books  or  by 


252  IRRIGATION  SYSTEMS 

field  costs  keepers  is  a  matter  on  which  there  is  much  difference 
of  opinion.  Where  the  work  is  of  sufficient  size  to  warrant  the 
use  of  field  timekeepers  it  is  probably  preferable  to  have  the  detail 
kept  by  them,  checking  against  the  totals  in  the  books.  If  all 
charge  vouchers  have  the  nature  of  the  items  given  in  sufficient 
detail  they  can  be  used  to  make  up  detail  costs  if  desired  without 
burdening  the  books  with  detail  accounts.  For  this  it  is  essen- 
tial that  the  filing  system  for  vouchers  be  such  that  they  can  be 
readily  found  from  the  reference  in  the  ledger.  Foremen  can  be 
instructed  to  note  the  character  of  the  work  performed  in  the 
time  book  or  in  daily  reports  where  the  crews  are  small  and  regu- 
lar timekeepers  are  not  kept.  Where  work  is  handled  under  con- 
tract the  company  generally  finds  it  desirable  to  keep  a  more  or 
less  close  account  of  the  costs  to  the  contractor.  This  is  usually 
done  by  the  field  inspector  or  instrumentman  in  connection  with 
his  other  duties.  .Such  costs  are  of  much  use  to  the  company  in 
determining  the  financial  conditions  of  the  contractor  and  in 
judging  fair  prices  for  similar  future  work.  It  is  generally  prefer- 
able to  obtain  such  details  in  the  more  informal  field  records 
rather  than  to  raise  detail  accounts  in  the  books.  . 

New  construction  works  such  as  extensions  or  enlargements 
should  be  handled  as  other  new,  work.  Such  work  is  distinct 
from  operation  and  maintenance.  There  is  a  considerable 
amount  of  construction  work  which  may  not  have  been  carried 
out  before  operation  began  so  that  in  the  earlier  years  both  con- 
struction and  operation  books  will  be  carried  separately.  The 
building  of  additional  laterals  will  be  such  an  item.  Later,  such 
work  can  be  handled  as  betterments. 

In  the  cases  of  some  large  projects  it  may  be  desirable  to  set 
up  books  for  separate  units  of  the  project.  This  will  apply  to 
the  functional  divisions  as  well  as  to  the  detail  accounts,  the 
accounts  of  each  unit  being  kept  as  for  separate  systems  except 
that  single  accounts  for  general  expenses  for  all  units  may  be 
carried. 

Various  clearing  and  suspense  accounts  will  also  be  required  in 
addition  to  those  handled  as  general  expenses.  These  will  include 
camp,  shop  and  storehouse  accounts  which  can  be  carried  as  dis- 
tinct accounts  and  distributed  to  proper  features  as  desired. 
The  extent  to  which  general  expenses  or  clearing  accounts  should 
be  distributed  to  features  is  often  a  difficult  one  to  decide.  Where 
they  are  made  on  a  fixed  percentage  basis  there  would  seem  to  be 


OPERATION  AND  MAINTENANCE  ACCOUNT      253 

little  advantage  in  such  distributions.  For  instance,  if  the  divi- 
sion of  the  cost  of  engineering  cannot  be  made  directly  to  features 
except  as  a  proportion  of  other  costs  little  is  gained  by  its  dis- 
tribution in  the  accounts.  If  on  larger  work  a  member  of  the 
engineering  force  is  engaged  continuously  sufficiently  long  so 
that  his  services  can  be  charged  directly  against  the  feature  such 
as  an  inspector  on  a  contract  lasting  more  than  1  month  the 
charge  can  be  made  directly  against  the  work.  The  utility 
accounts  prescribed  by  Western  commissions  usually  provide  for 
carrying  general  expenses  without  distribution  to  features.  In 
cost  statements  of  construction  the  percentages  represented  by 
engineering  and  overhead  are  of  as  much  use  if  stated  as  the  per- 
centage to  which  they  would  have  amounted  if  they  had  been 
distributed  as  if  they  had  actually  been  arbitrarily  prorated. 

REPORTS 

Annual  Reports. — The  reports  discussed  here  are  the  state- 
ments prepared  from  data  collected  and  recorded,  not  the 
methods  of  collection  and  recording,  which  have  been  previously 
discussed.  The  main  purpose  of  such  reports  is  to  summarize 
and  convey  the  information  regarding  the  operation  and  main- 
tenance of  the  system  to  those  interested,  principally  those  own- 
ing the  system,  who  are  also  more  usually  the  same  in  identity 
as  those  owning  the  land  served.  The  information  may  be  of 
two  kinds;  that  relating  to  expenditures,  and  that  relating  to  the 
results  accomplished  by  the  expenditures.  In  the  past  the  first 
kind  of  information  has  been  more  usual;  at  present  more  atten- 
tion is  being  paid  to  the  second  in  connection  with  the  first. 

The  practice  of  making  annual  reports  is  general.  The  year 
may  coincide  with  the  calendar  year  or  with  the  end  of  the  opera- 
tion season.  Many  irrigation  systems  print  annual  reports  for 
distribution  to  the  stockholders  and  water  users.  This  practice 
is  to  be  commended  as  it  furnishes  a  basis  on  which  the  users  can 
form  an  opinion  regarding  the  efficiency  of  the  management  and 
secure  a  better  understanding  of  some  of  the  problems  of  opera- 
tion. The  necessity  of  making  annual  reports  also  tends  to  im- 
prove the  keeping  of  records  on  which  they  may  be  based. 

There  is  much  difference  in  the  detail  of  such  reports.  The 
annual  project  reports  for  the  systems  of  the  U.  S.  Reclamation 
Service  are  in  much  detail,  giving  in  some  cases  some  of  the  rec- 


254  IRRIGATION  SYSTEMS 

ords  as  well  as  the  summary  and  conclusions  from  them.  Such 
reports  furnish  a  sufficiently  complete  record  of  the  operations 
for  the  year  as  to  be  useful  directly  as  a  source  of  information 
at  later  times  in  case  of  controversy  over  results.  Only  a  sum- 
mary of  such  reports  is  printed  in  the  annual  report  of  the  U.  S. 
Reclamation  Service  as  a  whole.  Many  systems,  such  as  irriga- 
tion districts  or  cooperative  companies,  print  the  financial  balance 
sheet  showing  only  the  revenues  and  expenses  without  compari- 
sons with  former  years  or  reasons  for  the  amounts  of  the  different 
items.  Other  systems  print  reports  intermediate  in  nature  but 
without  becoming  longer  than  will  be  read  with  interest  by  those 
concerned. 

Where  the  main  purpose  of  such  reports  is  for  distribution  to 
stockholders,  certain  points  in  which  the  stockholders  are  inter- 
ested should  be  kept  in  mind.  The  financial  interest  is  largely  in 
the  rate  of  assessment,  the  necessity  for  the  amounts  assessed,  the 
uses  made  of  the  funds,  explanations  why  this  year's  assessment 
differs  from  that  of  previous  years,  and  possibly  a  prediction  as  to 
conditions  in  the  coming  year,  although  this  is  usually  desirable 
only  in  case  unusually  large  expenditures  are  planned.  Any 
means  which  give  the  users  a  better  understanding  of  the  con- 
ditions of  operation,  the  policies  being  carried  out  and  the  uses 
made  of  funds,  aid  in  creating  a  better  feeling  in  support  of  good 
administration. 

The  annual  report  of  the  superintendent  of  Imperial  Water 
Co.  No.  1  for  1915  illustrates  the  subjects  which  may  be  treated. 
This  contained  about  18  printed  pages,  each  topic  having  side 
heads  so  as  to  be  readily  found,  with  the  treatment  to  the  point, 
yet  giving  the  necessary  facts.  Comparisons  with  the  four 
previous  years  were  also  given.  The  topics  were:  gross  expendi- 
ture and  average  force  employed ;  conditions  of  water  supply  for 
the  year;  total  water  used  by  months;  labor  conditions;  work  and 
results,  such  as  a  paragraph  each  on  cleaning,  clearing,  cutting 
brush,  repairing  canals,  new  construction,  reconstruction,  wooden 
and  concrete  structures,  canal  Ving,  dredging;  crop  acreage  by 
kinds  of  crops;  average  duty  of  water;  corral  account;  data  on 
individual  canals;  cost  of  operation  of  automobiles;  and  inven- 
tory. About  two  pages  of  water  equivalents,  general  rules  re- 
garding water  stock,  delivery  of  water  and  suggestions  in  regard 
to  irrigation  methods  were  added  at  the  end. 

In  the  1915  report  of  the  Twin  Falls  Canal  Co.  8  pages  of 


OPERATION  AND  MAINTENANCE  ACCOUNT      255 

small  size  are  used  to  give  the  usual  financial  statements  of 
receipts  and  disbursements,  resources  and  liabilities  and  inven- 
tory, followed  by  20  pages  of  what  is  called  explanation  and 
analysis  of  accounts,  giving  in  greater  detail  the  results  secured 
from  expenditures. 

The  Modesto  irrigation  district  printed  a  report  of  their  chief 
engineer  in  1916  following  the  completion  of  over  $500,000  of 
improvement  work.  The  costs,  including  overhead,  under  each 
contract,  with  descriptions  of  the  character  of  construction  used, 
were  given,  furnishing  information  from  which  the  water  users 
could  secure  an  understanding  of  what  had  been  accomplished. 

Circulars. — It  may  be  desirable  to  issue  circulars  to  the  stock- 
holders or  consumers  at  irregular  intervals.  Such  occasions  may 
arise  previous  to  voting  on  expenditures  for  improvements,  giving 
data  regarding  the  work  planned ;  when  changes  in  the  methods  of 
delivery  are  made;  or  in  notifying  each  stockholder  of  assess- 
ments. Temporary  matters  may  be  handled  through  local 
newspapers.  Where  the  information  is  official  or  it  is  desired  that 
it  be  kept  by  the  landowner,  circulars  are  preferable.  Such 
circulars  are,  however,  different  from  the  more  formal  and  per- 
manent rules  and  regulations. 

i  Records. — It  is  important  that  all  records  regarding  construc- 
tion and  operation  be  preserved.  This  can  be  done  in  the  general 
files  or  by  preparing  a  project  history  such  as  has  been  done  for 
each  of  the  systems  of  the  U.  S.  Reclamation  Service.  Such  records 
include  drawings  of  all  large  structures  as  actually  built,  records  of 
any  material  changes  made  in  maintenance,  particularly  for  por- 
tions which  may  be  underground,  and  records  of  water  diverted 
and  acreage  irrigated,  with  other  data  useful  in  establishing  water 
rights.  The  personnel  changes  from  year  to  year  and  such  facts 
should  be  compiled  for  later  use.  This  involves  but  little 
additional  time  or  expense  if  the  routine  drawings  and  records 
are  kept  in  good  form  and  carefully  filed  and  indexed.  The 
indexing  is  as  important  as  the  preparing  of  such  information,  as 
it  is  useless  unless  filed  so  as  to  be  accessible. 

REFERENCES  FOR  CHAPTER  IX 

Uniform  classification  of  accounts  for  water  corporations  of: 
Corporation  Commission  of  Arizona,  Phoenix,  Ariz. 
Railroad  Commission  of  California,  San  Francisco,  Cal. 
Public  Utilities  Commission  of  Idaho,  Boise,  Idaho. 


256  IRRIGATION  SYSTEMS 

Public  Service  Commission  of  Nevada,  Carson  City,  Nev. 

Railroad  Commission  of  Oregon,  Salem,  Ore. 

Public  Service  Commission  of  Washington,  Olympia,  Wash. 
Operation  and  Maintenance  Use  Book,  U.  S.  Reclamation  Service,  Wash- 
ington, D.  C. 

Manual  of  the  U.  S.  Reclamation  Service,  Washington,  D.  C. 
Standard  Classification  of  Accounts  of  Pacific  Gas  and  Electric  Co.,  San 

Francisco,  Cal. 
BLISS,  G.  H. — Character  of  Records  Kept  and  Importance  of  These,  1911, 

First  Conference  of  Operating  Engineers,  Boise,  Idaho. 
Report  of  Committee,   1913,   Conference  of  Operating  Engineers,   Great 

Fall,  Mont. 


APPENDIX 

RULES  AND  REGULATIONS 
IDAHO  IRRIGATION  DISTRICT 

BY-LAWS 
I 

Any  one  desiring  to  increase  or  decrease  the  flow  of  water  in  their  ditches 
must  give  the  manager  or  water  master  twenty-four  hours  written  notice, 
before  water  is  to  be  changed. 

Reason. — The  Idaho  Irrigation  system  is  not  provided  with  ample  waste- 
way;  therefore,  it  is  cheaper  to  be  careful,  have  a  steady  stream,  and  not  be 
assessed  for  damages  and  breaks. 

II 

Headgates. — Unnecessary  headgates  will  not  be  maintained  nor  operated. 
Reason. — It  is  impossible  to  regulate  with  safety  and  satisfaction,  two 
gates  where  one  gate  will  answer  all  practical  purposes. 

Ill 

Banks. — Patrons  are  warned  against  cutting  banks  of  canals  or  laterals, 
controlled  by  the  Idaho  Irrigation  District. 

Reason. — Because  it  is  a  penitentiary  offence,  and  will  be  vigorously 
prosecuted. 

IV 

Damages  to  Banks. — Anyone  allowing  stock  to  trample,  or  in  any  way 
damage  the  banks  of  the  canals  or  laterals  controlled  by  the  Idaho  Irriga- 
tion District,  will  be  held  responsible  for  damages. 

Reason. — To  protect  the  District. 

Fences. — Persons  having  fences  across  the  right-of-way  of  any  of  the  canals 
or  laterals  controlled  by  the  Idaho  Irrigation  District,  shall  make  proper 
gateway  on  banks  to  be  travelled  by  the  water  master;  they  shall,  also, 
keep  fences  from  in  any  way  retarding  the  velocity  of  the  water. 

Reason. — To  control  a  canal,  means  guarding  against  damage,  as  well  as 
delivering  water;  we  must  ride  the  banks  in  order  to  guard  against  breaks. 

VI 

Wasteways. — All  wasteways  into  the  Idaho  canal  system  must  drop  from 
a  box  or  flume  of  proper  construction,  to  be  approved  by  general  manager 
before  being  installed. 

Reason. — To  prevent  the  washing  down  of  the  banks,  and  the  filling  in  of 
the  canal. 

17  257 


258  IRRIGATION  SYSTEMS 

VII 

Structures. — Any  person  or  corporation  contemplating  the  building  of 
any  structure  over  the  canals  or  laterals  controlled  by  the  Idaho  Irrigation 
District,  shall  first  consult  manager  as  to  the  proper  plans. 

Reason. — To  safeguard  against  cutting  down  the  capacity  of  the  canals. 

VIII 

Control. — Gates,  checks  and  other  property  of  the  Idaho  Irrigation 
District  are  to  be  controlled  by  the  manager  and  water  masters  thereof. 
Any  person  who  breaks,  or  in  any  way  interferes  with,  the  locks,  gates  or 
checks,  will  be  punished  according  to  law. 

Reason. — The  checks,  gates,  locks,  etc.,  are  property  of  the  District; 
they  have  hired  a  manager  and  water  master  to  look  after  this  property  and 
give  the  patrons  of  the  Idaho  Irrigation  District  a  distribution  his  or  her 
holdings  entitle  them  to, 

IX 

Delivery. — Turning  the  water  to  which  any  person  or  persons,  is,  or  are, 
entitled  to,  into  the  headgates  of  such  person  or  persons  using  the  water 
from  this  system,  shall  be  deemed  and  considered  to  be  a  delivery  of  such 
water  to  any  person  or  persons.  The  district  will  not  deliver,  nor  undertake 
to  deliver,  water  to  any  person  who  does  not  own,  or  control,  a  lateral  or 
ditch,  connected  with  this  system,  which  will  safely  carry  the  water  which 
any  such  person  or  persons  may  desire  to  receive  from  this  system. 


Duty  of  Water  Users. — It  shall  be  the  duty  of  any  user  of  the  waters  of 
this  system  to  keep  his  laterals  or  ditches,  or  lateral  or  ditch,  as  the  case  may 
be,  in  such  order  and  repair  that  the  same  will  safely,  and  without  waste, 
carry  the  water  which  such  user  may  be  entitled  to. 

Approved  by  the  Board  of  Directors. 

TURLOCK  IRRIGATION  DISTRICT 

RULES  AND  REGULATIONS 

Governing  the  Distribution  of  Water  in  the  Turlock  Irrigation  District 
Management. — The  maintenance  and  operation  of  canals  and  works 
of  the  District  shall  be  under  the  exclusive  management  and  control  of  the 
superintendent,  appointed  by  the  Board  of  Directors,  and  no  other  person, 
except  his  employees  and  assistants,  shall  have  any  right  to  interfere  with 
said  canals  and  works  in  any  manner,  except  in  cases  of  a  special  order 
from  the  Board  of  Directors. 

Ditch  Tenders  and  Other  Employees. — The  superintendent  shall  employ 
such  ditch  tenders  and  other  assistants  as  may  be  necessary  for  the  proper 
operation  of  the  system.  Each  ditch  tender  shall  have  charge  of  his 
respective  section,  and  shall  be  responsible  to  the  superintendent.  From 


APPENDIX  259 

the  rulings  and  actions  of  the  ditch  tender,  an  appeal  may  be  made  to  the 
superintendent,  which  must  be  filed,  in  writing,  with  the  secretary,  upon 
request  of  the  superintendent. 

Application  for  Water. — At  the  beginning  of  the  irrigation  season,  the 
ditch  tender  shall  obtain,  from  each  irrigator,  a  written  application,  on 
forms  furnished  by  the  District,  specifying  the  number  of  acres  he  expects 
to  irrigate,  the  kind  of  crops,  and  such  other  information,  that  may  be  de- 
sirable. The  ditch  tender  shall  verify  this  acreage  and  shall  be  held  re- 
sponsible for  its  correctness. 

Acreage. — Only  land  leveled,  or  otherwise  prepared,  and  actually  irrigated, 
shall  be  included. 

Condition  of  Ditches. — Upon  said  application,  it  shall  be  the  duty  of  the 
ditch  tender  to  certify  whether  or  not  the  applicants'  ditches  are  in  proper 
condition  to  receive  water.  All  ditches  must  be  kept  free  from  weeds  and 
other  obstructions,  and  the  ditch  tenders  are  required  to  examine  the  same 
and  order  them  to  be  cleaned  before  water  is  turned  in.  Refusal  to  comply 
with  this  rule  will  be  sufficient  cause  for  refusal  to  turn  water  into  any 
ditch. 

Time  Limit  for  Use  of  Water. — Each  irrigator  will  not  be  allowed  to 
exceed  one-half  hour  to  irrigate  one  acre  of  land  in  alfalfa  and  other  crops 
requiring  flooding;  but  for  sweet  potatoes,  trees,  vines  and  gardens,  the 
District  will  endeavor  to  supply  water  as  required,  provided  that  the  total 
amount  of  water  delivered  to  such  crops,  in  one  month,  shall  not  exceed 
the  amount  of  water  available  for  each  acre  irrigated  in  the  District,  for 
said  month. 

Water  to  be  Used  Continuously,  Day  and  Night. — The  time  will  start  upon 
delivery  of  water  to  irrigator  and  water  must  be  used,  day  and  night,  con- 
tinuously, until  time  limit  expires. 

Notice  of  Delivery. — Each  irrigator  shall  be  notified  by  the  ditch  tender, 
at  least  twelve  hours  before  the  water  will  be  delivered  to  him,  and  further 
notice  of  any  change  in  time  of  delivery,  and  the  irrigator  who  fails  to  use 
his  allotment  of  water,  during  an  irrigation,  will  not  be  entitled  to  any  more 
water  at  any  future  irrigation,  than  if  he  had  used  his  full  share  at  the  time 
of  allotment. 

Water  Furnished  in  Rotation. — Water  shall  be  furnished  in  rotation  to 
each  irrigator,  except  by  agreement  between  adjoining  owners,  satisfactory 
to  the  ditch  tender,  and  which  will  not  change  the  time  of  irrigation  to 
other  irrigators,  commencing  at  the  lower  end  of  each  distributing  ditch. 
When  a  break  occurs  in  any  distributing  ditch,  the  irrigator,  to  whom  the 
water  is  given,  until  such  break  is  repaired,  shall  be  allowed  to  finish  before 
the  water  is  taken  from  him  and  he  shall  not  claim  another  irrigation  for 
that  run. 

Breaks  in  Distributing  Ditches. — The  party  irrigating  at  the  time  of  a 
break,  must  place  the  water  to  the  irrigator  next  in  rotation  and,  if  it  becomes 
necessary  to  shut  off  the  water  at  the  head  of  the  ditch,  the  ditch  tender 
must  be  notified.  If  this  is  done,  the  party  using  water  at  time  of  break, 
shall  receive  the  remainder  of  his  time,  when  the  break  is  repaired. 

Water  Receipts. — Any  person,  to  whom  water  is  offered,  must  sign  a 
receipt  therefor.  If  water  is  used,  the  receipt  must  show  upon  what  kind  of 


260  IRRIGATION  SYSTEMS 

crop,  and  for  what  length  of  time,  it  was  used;  and  if  it  is  not  used,  the 
receipt  must  specify  the  reason. 

Apportionment  of  Water. — The  water  will  be  apportioned  to  each  lateral 
by  the  superintendent,  and  the  ditch  tenders  will  be  in  charge  of  the  distri- 
bution of  the  same,  and  will  be  held  directly  responsible  by  the  super- 
intendent. *. 

Diverting  Gates  or  Side  Gates. — All  diverting  gates,  or  weirs  and  gates,  on 
all  private  ditches,  are  under  the  control  of  the  District,  but  the  District 
will  not  maintain,  or  repair,  gates,  or  weirs,  on  private  ditches.  The 
District  employees,  alone,  will  be  allowed  to  open  the  diverting  gates,  and 
they  have  full  authority  to  close  the  same  as  soon  as  the  requisite  amount  of 
water  for  each  irrigation  has  been  discharged.  Said  gates  will  be  supplied 
with  locks,  and  the  keys  shall  be  under  the  control  of  the  superintendent. 

Access  to  Land. — The  authorized  agents  of  the  District  shall  have  free 
access,  at  all  times,  to  lands  irrigated  from  the  canal  system,  for  the  purpose 
of  examining  the  canals  and  ditches  and  the  flow  of  water  therein. 

Right  of  Way. — No  fences,  ditches,  or  other  obstructions,  shall  be  placed 
across,  or  upon,  or  along,  any  canal  bank,  or  levee  of  any  canal  or  ditch, 
belonging  to  the  District,  without  the  special  permission  of  the  Board  of 
Directors  of  said  District.  Whenever  such  special  permission  shall  be 
granted,  it  shall  always  be  with  the  distinct  understanding  that  proper 
openings,  or  passageways,  shall  be  provided,  so  that  ditch  tenders  may 
pass  along  the  banks  of  said  canals  without  hindrance  and,  when  so  con- 
structed, the  ditch  tender  will  keep  them  closed  and  that  such  fence,  or 
obstruction,  must  be  removed,  whenever  requested  by  the  superintendent, 
or  Board.  The  superintendent  shall  have  the  right  to  remove  all  fences,  or 
obstructions,  constructed,  or  maintained,  contrary  to  these  provisions. 

Application  for  Gates. — No  openings  shall  be  made,  or  gates  placed,  in 
any  bank,  or  banks,  of  canals,  without  permission  from  the  Board  of  Direc- 
tors. Application  for  the  same  must  be  made  to  the  Board  of  Directors, 
and  filed  with  the  secretary,  on  blanks  furnished  by  said  District. 

Liability  of  District. — The  district  will  not  be  liable  for  any  damages 
resulting  directly,  or  indirectly,  from  any  private  ditch,  or  the  water  flowing 
therein;  but  its  responsibility  shall  absolutely  cease  when  the  water  is  turned 
therein,  according  to  these  rules  and  regulations. 

Liability  of  Irrigator. — Every  irrigator  shall  be  responsible  for  all  damages 
caused  by  his  wilful  neglect,  or  careless  acts. 

SECTION  592,  PENAL  CODE 

"Every  person,  who  shall,  without  authority  of  the  owner,  or  managing 
agent,  and  with  intent  to  defraud,  take  water  from  any  canal,  ditch,  flume  or 
reservoir,  used  for  the  purpose  of  holding,  or  conveying,  water  for  manu- 
facturing, agricultural,  mining,  irrigating,  or  generation  of  power,  or 
domestic  uses,  or  who  shall,  without  authority,  raise,  lower  or  otherwise 
disturb,  any  gate,  or  other  apparatus  thereof,  used  for  the  control,  or  meas- 
urement of  water,  or  who  shall  empty,  or  place,  or  cause  to  be  emptied, 
or  placed,  into  any  such  canal,  ditch,  flume,  or  reservoir,  any  rubbish,  filth, 
or  obstruction  to  the  free  flow  of  the  water,  is  guilty  of  a  misdemeanor," 


APPENDIX  261 

SAN  LUIS  POWER  &  WATER  COMPANY 

RULES  AND  REGULATIONS  FOB  WATER  USERS 
from  the 

SAN  Luis  WATER  &  POWER  COMPANY'S  SYSTEM 
Season  of  1913 

For  an  equitable  and  efficient  distribution  of  water  cooperation  is  neces- 
sary, and  a  strict  compliance  with  the  following  rules  and  regulations: 

1.  Customer  must  not  interfere  in  any  manner  with  the  employees  and 
property  of  the  Company. 

2.  Ditch  riders  will  have  charge  of  the  water  and  property  of  the  various 
water  districts,  and  are  responsible  only  to  the  Water  Superintendent. 

3.  All  water  will  be  apportioned  by  the  Superintendent  through  his 
ditch  riders,  to  the  water  users,  upon  requests  from  them  to  be  made  in  the 
following  manner: 

A.  Delivery  and  changes  in  delivery  of  water  must  be  requested  at 
least  24  hours  in  advance,  and  no  change  will  be  made  during  such  period. 

B.  Requests  must  be  made  by  application  to  the  Superintendent  or  the 
ditch  rider  of  the  district,  or  by  card  left  at  the  headgate  or  measuring 
device  of  the  consumer. 

C.  All  requests  shall  be  made  not  to  exceed  the  rate  of  4  acre-feet  of 
water  per  24  hours  for  each  160  acres,  or  less,  of  land  under  the  respective 
laterals  of  the  water  user's  application  for  water.     Users  whose  acres  are 
in  excess  of  160  acres  may  request  amounts  in  proportion  thereto.     Exchange 
between  neighbors  for  the  use  of  "heads"  is  greatly  desired  and  will  be 
encouraged  as  much  as  possible. 

D.  No  request  will  be  granted  unless  and  until  at  least   6   consumers 
have  made  similar  requests  for  water  from  the  same  main  lateral  to  be 
used. 

4.  Water  must  not  be  wasted.     Careless  and  wasteful  use  of  water  will 
not  be  tolerated,  and  the  water  will  be  shut  off  from  such  user  until  he 
prepares  to  make  better  use  of  the  same  to  the  satisfaction  of  the  Water 
Superintendent. 

5.  Complaints  of  water  users  shall  be  taken  up  first  with  the  ditch  rider 
of  the  district,  and  if  no  relief  is  afforded,  then  with  the  Water  Superintend- 
ent or  his  assistant.     In  case  of  further  complaint,  it  shall  be  taken  up  with 
the  General  Manager  of  the  Company  by  written  statement  to  the  same, 
and  in  no  less  than  three  days  after  the  act  complained  of  has  occurred. 

6.  The  limitation  in  the  contract,  to  1^  acre-feet  of  water  per  acre  for 
the  land  irrigated  during  the  entire  irrigation  season  will  be  enforced  in 
the  discretion  of  the  officers  of  the  Company. 

7.  No  crossing  of  a  canal  or  lateral  with  wagon  or  other  vehicles,  which 
may  injure  the  banks  of  same,  will  be  allowed,  and  any  such  acts  will  make 
the  party  upon  whose  land  the  act  occurs  liable  for  all  damages  so  done. 
Obstructions  and  bridges  may  be  built  upon  or  across  the  property  of  the 
Company,  but  only  upon  the  permission  and  under  the  supervision  of  the 
Company. 


262  IRRIGATION  SYSTEMS 

8.  All  water  measurements  will  be  made  in  the  unit  of  "acre-feet  per 
day  of  24  hours,"  to  all  consumers  alike.     All  gages  on  consumers'  measur- 
ing devices  will  be  plainly  marked  in  the  above  unit,  so  that  each  consumer 
can  read  his  rate  of  delivery  and  study  the  economic  conditions  in  the  use 
of  his  water. 

9.  Records  of  delivery  will  be  made  daily  by  the  ditch  riders  and  duplicate 
records  made  and  placed  at  the  measuring  device  of  each  consumer.     One 
copy  of  the  same  will  be  placed  weekly  on  file  in  the  office  of  the  Company. 

10.  Breaks  may  and  will  occur.     They  will  always  be  promptly  repaired 
and    regular    conditions   will    be    restored    as    soon    as    possible.     Great 
assistance  will  be  given  if  all  breaks  are  reported  promptly  to  the  Water 
Superintendent. 

11.  In  case  of  shortage  of  water  from  any  cause,  either  temporary  or  for 
the  season,  the  consumer  will  be  notified  as  soon  as  possible,  and  rotation  of 
water  to  districts  may  be  made  by  the  Water  Superintendent,  and  then 
water  must  be  used  by  the  consumer  in  the  rotation  periods  provided. 

12.  Water  turned  into  the  private  ditch  of  the  consumer   will  be  con- 
sidered as  delivered  to  the  water  user  and  for  the  land  covered  by  the  water 
application.     The  Company's  liability  ceases  upon  such  delivery. 

13.  Party  and  joint  ditches  must  be  properly  regulated  and  to  the  satis- 
faction of  the  Water  Superintendent,  before  water  is  delivered  into  the  same. 

14.  Crop  data  and  duty  of  water  for  the  entire  project  will  be  obtained 
with  your  cooperation  by  the  Water  Superintendent,  and  summary  will  be 
furnished  each  user  at  the  end  of  the  season. 

15.  Access  to  all  lands  of  the  water  users  of  the  project  shall  never  be 
denied  to  the  authorized  agents  of  the  Company. 

16.  Service  and  impartiality   is  what  is  wanted,  and  it  can  only  be  ob- 
tained by  cooperation  and  strict  compliance  with  the  above  rules  and 
regulations. 

FRESNO    CANAL  AND   IRRIGATION   COMPANY 

SUPPLEMENTAL  ORDER 

IT  IS  HEREBY  ORDERED  that  the  following  information,  rules  and 
regulations  for  The  Fresno  Canal  and  Irrigation  Company  and  its  water 
users  be  established  by  The  Fresno  Canal  and  Irrigation  Company,  effective 
April  1,  1914: 

INFORMATION,  RULES  AND  REGULATIONS — FRESNO  CANAL  AND  IRRIGATION 
COMPANY  AND  ITS  WATER  USERS 

Rule'l.  Operation  and  Maintenance  of  System. — The  Fresno  Canal  and 
Irrigation  Company  will  operate  and  maintain  all  diversion  works,  main 
canals,  branch  canals  and  laterals,  where  it  is  the  established  duty  of  the 
Company  to  do  so. 

On  any  portion  of  the  distributing  system  which  the  Company  is  not  now 
obligated  to  maintain  and  operate,  any  user  may  request  the  Company  to 
assume  control.  The  Company  will  then  approach  all  users  suggesting  a 


APPENDIX  263 

sum  for  which  the  Company  will  place  the  ditch  in  proper  condition  and, 
further,  the  rate  per  acre  per  annum  for  which  in  the  future  the  maintenance 
and  operation  will  be  assumed.  Should  this  be  agreed  to  unanimously, 
the  Company  will  forthwith  assume  control.  It  may  be  arranged  that  either 
the  users  or  the  Company  shall  put  the  ditch  initially  in  good  condition,  the 
actual  cost  to  be  paid  by  the  users. 

Should  the  arrangement  mentioned  in  the  preceding  paragraph  fail  of 
agreement  by  all  parties,  the  user  or  users  desirous  of  this  change  may  apply 
to  the  Railroad  Commission,  which  will  decide  whether  it  will  be  for  the 
furtherance  of  public  convenience  to  grant  the  application;  and  if  it  be 
granted,  will  fix  the  payment  and  rates  due  the  Company  for  such  increased 
service  and  the  time  and  method  of  deposit  of  the  payment  for  such  service. 

The  Company  retains  the  right  to  supervise  the  delivery  of  water  to  all 
individuals  who  make  direct  payment  to  it,  wherever  in  the  flow  of  its  water 
supply,  and  will  require  that  all  distributaries  not  under  its  direct  control 
shall  be  maintained  in  proper  condition  for  the  distribution  of  water  to 
individual  consumers. 

Rule  2.  Definition  of  "Pro  Raia"  Delivery. — A  "pro  rata"  delivery 
means  a  simultaneous  flow  available  at  a  point  nearest  on  the  Company's 
system  for  the  use  of  each  and  every  consumer,  in  an  exact  proportion  of  the 
total  amount  available,  based  on  the  individual's  right  to  receive,  as  fixed 
by  acreage,  contract,  payment  or  otherwise.  This  method  may  be  applied 
to  all  or  a  part  of  the  system. 

Rule  3.  Definition  of  "Rotation." — "Rotation"  means  that  method  of 
delivery  whereby  water  is  carried  through  a  portion  of  the  distribution 
system,  for  a  portion  of  the  time,  in  larger  amount  than  otherwise  available, 
the  aim  being  to  deliver  to  each  consumer  ultimately  as  exact  a  proportion 
as  by  "pro  rating." 

Rule  4.  Protection  and  Delivery  of  Full  Supply. — The  Company  will 
endeavor  at  all  times  to  divert  all  water  legally  within  its  right  into  the  canals 
of  the  system  up  to  the  aggregate  amount  of  demands  upon  it,  and  will  use 
every  endeavor  to  protect  the  water  supply  available,  and  transmit  same  in 
proportional  amount  to  the  points  on  its  system  nearest  by  the  established 
routes  to  its  individual  consumers.  When  sufficient  water  is  available  to 
supply  all  demands,  it  will  be  distributed  at  all  division  points  and  turnouts 
to  branch  canals  and  laterals  in  a  proportional  part  of  the  total  flow  avail- 
able, allowing  for  seepage  loss,  this  proportion  being  based  upon  the  acreage 
and  recognized  rights  to  demand  service  upon  each  part  of  the  system. 
That  is,  the  total  amount  that  is  determined  can  be  delivered  from  the  supply 
available,  will  be  ratably  divided. 

Rule  5.  Delivery  of  Intermediate  Supply. — When  the  supply  available  at 
the  hands  of  the  Company  is  insufficient  to  fully  supply  demands,  but  is 
above  50  per  cent,  of  the  amount  demanded,  water  will  be  pro  rated  between 
distributaries  of  more  than  200  cubic  feet  per  second  capacity,  and  may  be 
rotated  between  smaller  distributaries. 

Rule  6.  Delivery  of  Supply  Below  50  Per  Cent. — When  the  supply  avail- 
able is  not  sufficient  to  satisfy  50  per  cent,  of  the  demand,  the  Company 
may  rotate  in  all  portions  of  the  distribution  system.  So  far  as  is  possible, 
a  forecast  will  be  made  of  the  available  water  supply,  and  rotation  between 


264  IRRIGATION  SYSTEMS 

•\ 

main  canals  shall  be  so  planned  as  to  provide  a  full  head  in  each  canal 
during  the  period  of  flow,  which  period  will  be  varied  in  accordance  with  the 
amount  of  the  total  supply  and  as  many  as  may  be  of  the  branch  canals  and 
laterals  will  be  filled  simultaneously,  and  it  will  be  planned  to  provide  a 
continued  flow  for  sixteen  or  eighteen  days. 

Rule  7.  Notice  of  Water  Delivery. — The  Company  will  provide  bulletin 
boards  at  convenient  points,  and  will  give  notice  thereon,  and  by  other 
feasible  means,  of  the  time  of  beginning  and  ending  of  rotation  periods 
upon  each  of  the  branch  ditches  and  upon  all  parts  of  the  system  where 
delivery  is  made  by  the  Company  direct  to  the  individuals.  The  Company 
will  give  information  of  the  beginning  and  duration  of  each  run  of  water 
sufficiently  in  advance  for  the  guidance  of  consumers.  Such  publication  of 
rotation  periods  shall  be  not  less  than  three  days  before  the  beginning  of 
the  period,  except  in  case  of  emergency,  when  the  best  endeavor  will  be  made 
by  the  Company  through  all  means  in  its  power  to  spread  the  necessary 
information. 

Rule  8.  Rotation  of  Service  in  Cycles. — As  nearly  as  is  practicable,  each 
individual  or  aggregation  of  individuals  will  be  given  a  ratable  service  within 
a  single  season ;  provided  this  has  not  been  done,  the  rotation  shall  continue 
in  cycles;  that  is,  those  receiving  a  deficient  supply  in  the  preceding  season 
shall  be  served  in  precedence  of  others  during  the  following  year. 

Rule  9.  Rotation  Delivery  to  Individuals. — Between  the  individual  users 
along  the  main  canals  of  the  Company  and  on  minor  distributaries  where 
each  individual  may  use  the  full  flow  of  such  distributary,  delivery  shall  be 
by  rotation,  commencing  generally  at  the  farther  end  of  such  laterals,  water 
being  delivered  to  consumers  in  turn,  the  length  of  time  being  in  accordance 
with  the  acreage  and  right.  On  larger  distributaries  delivery  shall  be  limited 
to  a  rate  of  4  cubic  feet  for  24  hours  to  each  20-acre  lot,  and  to  as  many 
irrigators  simultaneously  as  is  possible  with  the  supply  available.  When 
rotation  has  been  resorted  to  in  delivery  to  the  main  branches  the  time  period 
shall  be  reduced  proportionally,  but  the  endeavor  will  be  to  deliver  heads 
sufficient  in  amount  for  the  most  beneficial  use. 

Water  must  be  used  continuously  day  and  night  and  should  irrigation 
be  completed  before  the  scheduled  termination  of  a  period  of  flow,  the 
superintendent  or  ditch  tender  should  be  notified  to  have  the  delivery 
stopped. 

Consumers  are  responsible  for  all  water  delivered  to  them  and  must  make 
beneficial  use  of  the  entire  amount,  allowing  no  avoidable  waste. 

Rule  10.  Deviations  from  Schedules. — Deviation  from  the  established 
schedule  will  be  allowed  only  by  previous  arrangement,  and  when  the  efficiency 
of  the  system  is  not  thereby  seriously  impaired,  so  that  irrigators  desiring  a 
less  flow  for  a  length  of  time  may  be  accommodated,  and  in  case  an  irrigator 
is  not  ready  for  water  when  his  turn  is  scheduled,  he  may  exchange  with 
another. 

Rule  11.  Credit  for  Non-use. — When  a  water  user  has  not  taken  advantage 
of  the  supply  available  during  any  period,  nor  arranged  an  exchange  with 
another  user,  he  may  be  supplied  during  the  next  period  provided  there  is 
more  water  available  than  sufficient  to  supply  all  demands. 

Rule   12.  Control   over   System. — (a)  The  structures  on  the  Company's 


APPENDIX  265 

canal  system  will  be  under  the  exclusive  control  of  the  Company's  em- 
ployees. The  superintendent  will  give  full  instructions  to  ditch  tenders 
in  regard  to  all  changes  to  be  made  in  the  flow  of  water.  Any  other  person 
tampering  with  or  in  any  manner  changing  the  arrangement  of  gates  or 
flashboards  in  any  turnout,  check,  drop  or  other  structure  of  the  Canal 
Company,  will  be  dealt  with  according  to  law. 

(6)  The  superintendent  may  grant  special  permission  from  time  to  time 
to  irrigators  to  alter  flashboards  or  gates,  which  permission  should  be  in 
writing  or  by  messenger  later  substantiated  by  a  written  communication, 
and  will  be  for  the  specified  time  only.  It  may,  however,  be  arranged  that 
a  number  of  users  on  a  lateral  shall  change  their  gates  in  compliance  with  an 
established  rotation  schedule. 

Rule  13.  Deductions  for  Over-supply. — If  any  consumer  shall  have  been 
found  through  his  own  or  any  other  unauthorized  person's  acts  to  have 
obtained  more  than  his  ratable  supply  of  water,  the  amount  above  his 
proper  supply  shall  be  deducted  from  later  runs,  to  compensate  the  other 
consumers. 

Rule  14.  Unit  of  Measurement. — The  unit  of  measurement  will  be  the 
cubic  foot  per  second. 

Rule  15.  Measurement  of  Water  and  Records. — Gaging  stations  will  be 
established  at  points  in  the  main  and  branch  canals.  At  all  practicable 
points  in  the  laterals,  weirs  or  other  measuring  deyices  will  be  placed  in 
sufficient  number  to  arrive  at  a  close  approximation  of  the  amounts  of  water 
delivered  at  all  points  upon  the  system  of  the  Company.  Records  shall  be 
kept  in  the  office  of  the  Company  showing  throughout  the  season  the  amount 
of  water  that  has  passed  each  such  point,  and  will  be  carried  to  totals  by 
months,  and  each  interested  party  will  on  request  be  informed  at  the  close 
of  the  season  of  the  amount  of  water  which  he  must  reasonably  have  re- 
ceived in  so  far  as  the  jurisdiction  of  the  Company  extends. 

Rule  16.  District  Superintendents  and  Ditch  Tenders. — The  official  per- 
sonnel of  the  Company  who  will  deal  with  consumers  will  include  two  district 
superintendents,  whose  duty  will  be  the  supervision  of  the  individual  ditch 
tenders  and  the  keeping  of  records  of  the  amounts  of  water  turned  into 
canals,  branches  and  laterals  and  chargeable  to  individual  consumers.  A 
sufficient  number  of  ditch  tenders  will  be  employed  to  visit  once  daily 
practically  every  point  on  the  system  where  water  is  running.  Their  duty 
will  be  to  follow  strictly  the  instructions  of  the  district  superintendents  in 
the  delivery  of  water  to  the  various  consumers,  to  make  gage  and  weir  read- 
ings at  all  established  measuring  points,  to  guard  and  care  for  the  property 
of  the  Company  used  in  the  distribution  of  water,  to  see  that  water  is  not 
wasted,  to  report  any  case  of  such  wasting  of  water  by  consumers  and 
trespassers  upon  any  part  of  the  Company's  system,  tampering  with  gates 
and  flashboards  and  complaints  made  along  their  respective  beats.  Com- 
plaints may  also  be  made  directly  to  the  Company's  office,  in  writing  or  by 
phone. 

Rule  17.  Relations  Between  Company  and  Consumers. — All  officials  of 
the  Company  are  instructed  to  aid  the  water  users  in  every  manner,  and  to 
courteously  and  respectfully  consider  all  criticisms  and  suggestions.  The 


266  IRRIGATION  SYSTEMS 

Company  will  meet  with  the  desires  of  each  consumer  in  so  far  as  it  can  do 
so  with  justice  to  all  interested  parties. 

The  foregoing  Supplemental  Opinion  and  Order  are  hereby  approved  and 
ordered  filed  as  the  Supplemental  Opinion  and  Order  of  the  Railroad  Com- 
mission of  the  State  of  California. 

Dated  at  San  Francisco,  California,  this  28th  day  of  March,  1914. 


INDEX 


Access  to  land,  175 
Accounts,  243,  247 

schedule  of,  250 
Account  numbers,  251 
Accuracy  of  measurements,  141 
Administration  of  streams,  227 
Agricultural  aid  to  irrigators,  237 
Algae,  20 

Alkali,  action  on  concrete,  56 
Amity    canal,    lateral    organization, 

123 

Annual  reports,  253 
Application  for  water  delivery,  113, 

180 
Apportionment       of       construction 

charge,  188 

of  water  during  shortage,  182 
Aquatic  growths,  19 
cutting,  21 
dragging,  22 
harrowing,  22 
sun-killing,  23 
Area,  classification  of,  191 

handled  by  ditch-riders,  86,  89, 

90 

Arsenic  for  controlling  vegetation,  30 
Artificial  silting,  14 
Automatic  gauges,  139 


B 


Badgers,  40 

Banks,  canal,  maintenance,  25 
Barnyard  millet,  24 
Beats,  of  ditch  riders,  87 
Beneficial  use,  limifs  of,  195 
Benefit,  basis  of  charges,  189 
Bermuda  grass,  27 
Betterments,  definitions  of,  245 
Billings    Land     &    Irrigation    Co., 
canal,  9 


Bitter  Root  Valley  Irrigation  Co., 

screen,  35 

Blowing  soils  in  canal  banks,  32 
Breaking  rules,  penalty  for,  186 
Bridges  for  gauging  stations,  130 

over  canals,  72 
Brush  rip-rap,  12 
Burrowing  animals,  36 


California  Railroad  Commission,  re- 
quired accounts,  244 

decision  of,  122 

reports  of,  200 
Canals,  control  of,  174 
Canal  gauges,  138 

banks,  maintenance,  25 

hydrography,  127 

measurement,  methods,  134 

moss,  19 

operation  under  pumping  plants, 
230 

ratings,  control  of,  131 

rating  stations,  128 

screens,  34 

Carey  act  projects,  charges,  188 
Carriage  of  water,  accounts,  250 
Census  of  crops,  220 
Charges,  construction,  payment,  187 

flat  rate  and  benefit,  189 

operation  and  maintenance,  194 
Cheat  grass,  26 
Checks,  affect  on  silting,  14 

use  of,  209 

Chemicals,  use  on  vegetation,  23,  29 
Cippoletti  weirs,  148 
Circulars,  255 
Classification  of  costs,  198 

of  irrigable  area,  191 
Clearing  accounts,  251,  252 
Clerical  organization,  83,  96 
Coefficients  for  orifices,  153 


267 


268 


INDEX 


Colonization,  235 
Compensation  of  ditch  riders,  93 
Complaints,  218 

rules  for,  184 
Computation  of  measurement,  143, 

158 
Concrete,  action  of  alkali  on,  56 

lining,  maintenance  of,  71 

structures,  life  of,  56 

use  of,  59 
Construction  charges,  187 

cost  accounts,  251 
Continuous  delivery,  102 
Control  of  canal  ratings,  131 

of  canal  system,  174 

of  laterals,  119 
Cost  of  maintenance,  1 

measurement,  142 

operation  and  maintenance,  2 

pumping,  234 

relative  of  wood  and  concrete, 
60 

service  in  operation,  199 

variations  from,  202 
Crop  statistics,  220 
Current  meters,  use  of,  134 
Cutting  around  structures,  68 


Damages  for  failure  to  deliver  water, 

5 

liability  for,  4 
value  of,  5 
from  waste  water,  6 
Dams,  maintenance  of,  63 
Delivery  of  water  during  shortage, 

109 

forms  used  for,  113 
gates,  used  for  measurement, 

152 

general,  99 

measurement  of,  112,  141 
methods,  summary,  118 
on  demand,  109 
period  of,  181 
rules  for,  178 
special  methods,  112 
storage,  227 


Demand  charges,  197 

delivery  on,  109 
Dethridge  meter,  157 
Development  of  water  accounts,  250 

rate  of,  236 

Devices,  measuring,  142 
Distribution  accounts,  250 
Ditch  riders,  85 

records,  160 
time  employed,  93 
Diversion  dams,  maintenance  of,  64 
Dragging  for  canal  vegetation,  22 
Drainage,  225 

accounts,  251 
Duty  of  water,  factors  affecting,  195 

E 

Easements  for  rights  of  way,  44 
Electric  power  for  pumping,  233 
Engineering  organization,  82,  94 
Equipment  of  gauging  stations,  129 

pumping  plants,  232 
Erosion  in  canals,  11 

at  structures,  67 


Farms  served  per  ditch  rider,  92 

size  of,  236 
Fences,  cost  of,  46 
Fencing  canals,  43 
Fish  ladders,  66 

screens,  65 

Fixed  rotation  schedule,  108 
Flat-rate  payments,  189,  197 
Floats,  use  of,  136 
Flumes,  life  of,  52 

maintenance  of,  69 

steel,  life  of,  53 

wood,  life  of,  52 
Forms  for  delivery  of  water,  113 

measurement,  159 
Form  of  organization,  effect  on  pay- 
ments, 188 
Fording  canals,  74 
Freeboard  in  canals,  amount  of,  10 
Fresno    Canal   and    Irrigation    Co., 
rules,  262 


INDEX 


269 


Gates,  location  of,  176 

Gauges,  138 

Gauging  stations,  129 

Gophers,  37 

Grain,  poisoned,  41 

Grand     Valley     project,     puddling 

canals,  15 

Gravel  canal  linings,  11 
Grazing  of  canal  banks,  28 
Ground  squirrels,  38 
Gypsum  formations,  canals  in,  10 

H 

Harrowing  canal  vegetation,  22 
Headgates  for  measurement,  152 
Headworks,  maintenance  of,  64 
Huntley  project,  puddle  linings,  15 
Hydrographic  records,  139 
Hydrography,  125 


Ice,  operation  with,  217 

Idaho    Irrigation   district,    rules  of, 

257 

Imperial  Valley,  handling  silt  in,  17 
Imperial  Water  Co.  No.  1,  report  of, 

254 
Individual  deliveries,   measurement 

of,  141 

Integration,  method  of  gauging,  134 
Interest  on  payments,    206 
Interruptions  in  service,    182 
Irrigable  area,  191 
Irrigation  districts,  charges,  189 


Johnson  grass,  27 
June  grass,  27 


Land  ownership  by  operating  force, 

238 
Laterals  control  of,  119 

delivery  on,  up  or  down,  107 

maintenance  of,  177 

organizations,  119 

rotation  between,  106 
Legal  fences,  46 


Length  of  ditch  riders  beats,  92  . 
Liability  of  company,  rules  for,  185 

irrigators,  rules  for,  185 
Lichens,  21 
Life  of  structures,  52 
Limits  of  beneficial  use,  195 
Lined  canals,  maintenance  of,  71 
Linings  for  canals,  11 
Location  of  gates,  176 
Locking  turnouts,  215 
Longwell,    J.   S. — method   of   canal 
rating,  131 

M 

Maintenance,  cost  of,  1 

definition  of,  245 

diversion  dams,  64 

flumes,  69 

general,  1 

headworks,  64 

laterals,  177 

lined  canals,  71 

reservoirs,  63 

structures,  50,  66 
Manager,  qualification  of,  83 
Measurement  of  deliveries,  112,  141 

effect  of  rates  on,  196 

rules  for,  181 

special  devices,  156 

of  water,  125 
Mice,  field,  40 
Minidoka  project,  brush  riprap,  12 

canal  silting,  16 

rates,  205 

turnout  numbers,  215 
Minimum  period  of  delivery,  181 
Modesto   Irrigation  District,  report 

of,  255 
Moss,  19 

cutting,  21 

dragging,  22 

harrowing,  23 

sun-killing,  23 
Mowing  canal  banks,  29 
Muskrats,  39 

N 

North  Platte  project,  blowing  soils, 
33 


270 


INDEX 


Notes  for  canal  gauging,  139 
Notices  of  water  delivery,  117 
Numbering  canals  and  turnouts,  214 


O 


Oiling  canals,  23 

Okanogan  project,  rates,  205 

Operation  and  maintenance  charges, 

194 

costs,  198 

organization,  82,  84 
policy,  determination  of,  240 
Oregon    Railroad    Commission,    ac- 

ceunts,  245 
Organization  chart,  81 

size  of,  96 
Organizations,  79 
Orifice  headgates,  154 
Orifices  submerged,  152 
Overtopping  canal  banks,  10 
Ownership    of    land    by    operation 
force,  238 


Pacific  Gas  &  Electric  Co.,  accounts, 

245 

Pasturing  canal  banks,  28 
Patrolmen,  85 

Payment   of   construction    charges, 
187 

operation  charges,  194 

terms  of,  183,  192,  206 
Period  of  delivery,  181 

rotation  delivery,  104 
Pipe,  concrete,  life  of,  57 

steel,  life  of,  59 

wood,  life  of,  53 
Pocket  gophers,  37 
Poisoning,  rodents,  40 
Policy,  determination  of,  240 
Pond  weeds,  19 
Power  for  pumping,  233 
Prairie  dogs,  40 
Priming  canals,  6 
Puddle  lining,  15 
Pumping,  cost  of,  234 

plants,  equipment,  232 

operation  of,  230 


Q 

Quantity  rates,  197 

R 

Rate  of  development,  236 
Rates,  effect  on  measurement,  196 
Rating  curves,  control  of,  131 

stations,  128 
Ratio  of  demand  and  service  costs, 

199 
Records,  255 

for  canal  gaugings,  139 

of  delivery,  158 
Rectangular  weirs,  148 
Registers,  automatic,  139 
Regulations,  173 
Replacements,  definition  of,  245 

selections  of,  59 
Reports,  253 
Requirements  of  measuring  devices, 

146 

Reservoirs,  maintenance  of,  63 
Restoring  canal  cross  sections,  13 
Restricting  use  of  water,  239 
Rights  of  way,  44,  176 

fencing,  43 
Rotation  between  laterals,  106 

delivery,  103 

schedules,  104,  108 
Rules,  173 

penalty  for  breaking,  186 
Russian  thistle,  25 

S 

Salt  River  Project,  pasturing  canal 

banks,  28 
San  Luis  Power  &  Water  Co.,  rules, 

261 

Sawing  canal  vegetation,  21 
Schedule  of  accounts,  250 

for  rotation  delivery,  104,  108 
Screens  for  canals,  34,  65 
Sediment,  13 
Seeding  canal  banks,  31 
Seepage  losses,  16 
Semi-aquatic  plants,  24 
Service  charges,  198 

interruptions  in,  182 
Serviceable  life  of  structures,  52 


INDEX 


271 


Settling  of  canal  banks,  6,  8 
Sheep  on  canal  banks,  28 
Shortage,  apportionment  during,  182 

delivery  during,  109 
Shutting  water  out  of  canals,  7 
Side-hill  canals,  8 
Silt,  13 

removal  of,  16 

Single  point  method  of  gauging,  134 
Size  of  farm,  236 

organization,  96 
Sloughing  of  canal  banks,  7 
Soil,  affect  on  rates,  204 
Special  delivery  methods,  112 

measuring  devices,  156 
Squirrels,  ground,  38 
Staff  gauges,  138 
Steel  flumes,  life  of,  58 

life  of,  58 

pipe,  life  of,  59 
Stock  water,  213 

rules  for,  182 

Storage,  running  in  streams,  227 
Structures,  erosion  at,  67 

maintenance  of,  50,  66 

selection  of  type,  59 

undercutting,  68 
Strychnine  poisons,  41 
Submerged  orifices,  152 
Submergence  of  weirs,  149 
Suffocation  of  rodents,  42 
Sun-killing  of  canal  vegetation,  23 
Sunny  side  project,  gravel  linings,  12 
Surface  floats,  use  of,  136 
Sweet  clover,  26 


Tap  box,  measurement  with,  155 

Telephones,  75 

Terms  of  payment,  183,  192,  206 

Trapping  rodents,  42 

Tules,  24 

Tumbling  weeds,  25 

Turlock    Irrigation    District — canal 

cleaning,  18 
rules,  258 

Turnouts,  measurement  with,  155 
Twin  Falls  Canal  Co.,  report,  254 
Two-point  method  of  gauging,  134 


U 

U.  S.  Reclamation  Service,  accounts, 

248 

annual  reports,  253 
operation      and      maintenance 

costs,  201,  203 
rates,  201 
standard  orifices,  154 

weirs,  150 

telephone  lines  of,  76 
terms  of  payment,  193 
Umatilla  project,  weed  screen,  36 
Unstable  formations,  canals  in,  8 
Use  of  water,  factors  affecting,  195 
restrictions  on,  239 


Variations  in  rates,  202 
Vegetation  in  canals,  19 
on  canal  banks,  25 
Venturi  meter,  157 
Verticals  used  in  gauging,  137 

W 

Waste,  rules  for,  183 

water  from  farms,  210 
responsibility  for,  6 
Wasteways,  212 
Water  butter-cup,  20 

delivery,  computations,  158 
forms  use  for,  159 

grass,  24 

ledger  cards,  170 

Waterproofing  concrete  surfaces,  57 
Weed  screens,  34    - 
Weirs,  148 
Willows,  27 
Winter  operation,  216 
Wood  flumes,  life  of,  52 

stave  pipe,  life  of,  53 

structures,  life  of,  55 
use  of,  59 


Yuma  project,  removing  silt,  18 

Z 
Zanzero,  85 


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a 


1 

ir^ 


27  1950 


UNIVERSITY  OF  CALIFORNIA 

DEPARTMENT  OF  CIVIL  ENGINEERING 

BERKELEY.  CALIFORNIA 

UNIVERSITY  OF  CALIFORNIA  LIBRARY 


